| resistance in lycopersicon peruvianum to isolates of mi gene-compatible meloidogyne populations. | root-knot nematode resistance of f progeny of an intraspecific hybrid (lycopersicon peruvianum var. glandulosum acc. no. 126443 x l. peruvianum acc. no. 270435), l. esculentum cv. piersol (possessing resistance gene mi), and l. esculentum cv. st. pierre (susceptible) was compared. resistance to 1) isolates of two meloidogyne incognita populations artificially selected for parasitism on tomato plants possessing the mi gene, 2) the wild type parent populations, 3) four naturally occurring resistan ... | 1990 | 19287762 |
| effects of root-knot nematodes on areca catechu. | no root galling or egg mass formation was noted on betel palm (areca catechu) 3 or 9 months after inoculation with meloidogyne arenaria, m. hapla, m. incognita races 1 and 3, or m. javanica. compared with uninoculated controls, a reduction (p </= 0.05) in fresh root weight was noted after 3 months with m. incognita race 1 but not with other species or races, no differences (p </= 0.05) in root weight between controls and inoculated plants were observed at 9 months, nor were any differences found ... | 1989 | 19287679 |
| crops uncommon to alabama for the management of meloidogyne arenaria in peanut. | in a 1987 field study juveniles of meloidogyne arenaria assayed at the time of peanut harvest were almost undetectable in plots planted with american jointvetch (aeschynomene americana), castor bean (ricinus communis), partridge pea (cassia fasiculata), sesame (sesamum indicum), and cotton (gossypium hirsutum), whereas plots with peanut (arachis hypogaea) averaged 120 juveniles/100 cm(3) soil. application of aldicarb in peanut resulted in an average of 27 juveniles/100 cm(3) soil. in 1988 all pl ... | 1989 | 19287678 |
| host suitability of soybean cultivars for meloidogyne incognita and m. arenaria. | the suitability of five maturity group (mg) iii and five mg iv soybean, glycine max, cultivars as hosts for meloidogyne incognita and m. arenaria was evaluated in a greenhouse. 'forrest', a mg v cultivar, was used as the standard of comparison for m. incognita resistance. with m. incognita, root-gall and egg-mass indices and reproductive factors for 'asgrow 3307', 'ffr 398', and 'pioneer 9442' were comparable with those found on forrest. meloidogyne arenaria reproduction was lower (p </= 0.05) o ... | 1989 | 19287669 |
| resistance to meloidogyne arenaria in arachis spp. germplasm. | field and greenhouse evaluations of 116 wild arachis spp. genotypes demonstrated the presence of resistance to reproduction of the root-knot nematode meloidogyne arenaria race 1. resistance in greenhouse tests was based on test lines having </= 2.5% of the number of eggs per gram of roots as did the susceptible a. hypogaea cv. tamnut 74. in field tests, resistant genotypes were identified on the basis of having lower (p = 0.05) final nematode population densities than did tamnut 74. resistance w ... | 1989 | 19287667 |
| suitability of small grains as hosts of meloidogyne species. | seven cultivars of wheat, five of oat, one of rye, and four of barley were tested as hosts for meloidogyne incognita, m. javanica, or m. arenaria under greenhouse conditions where soil temperature ranged from 21 to 34 c. reproduction rates of all nematode species were high on all cultivars, except m. javanica and m. arenaria on 'brooks' and 'florida 501' oat. meloidogyne incognita and m. javanica produced more eggs on roots of 'rutgers' tomato than on cultivars of wheat, oat, rye, or barley. | 1989 | 19287666 |
| effect of carbamate, organophosphate, and avermectin nematicides on oxygen consumption by three meloidogyne spp. | second-stage juveniles (i2) of meloidogyne arenaria consumed more oxygen (p </= 0.05) than m. incognita j2, which in turn consumed more than m. javanica j2 (4,820, 4,530, and 3,970 mul per hour per g nematode dryweight, respectively). decrease in oxygen consumption depended on the nematicide used. except for aldicarb, there was no differential sensitivity among the three nematode species. meloidogyne javanica had a greater percentage decrease (p </= 0.05) in oxygen uptake when treated with aldic ... | 1989 | 19287640 |
| screening subterranean clover (trifolium spp.) germplasm for resistance to meloidogyne species. | this study was conducted to identify lines of subterranean clover (trifolium spp.) with resistance to meloidogyne arenaria (neal, 1989) chitwood, 1949, race 1; m. incognita (kofoid and white, 1919) chitwood, 1949, race 3; and m. javanica (treub, 1885) chitwood, 1949. a collection of 134 subterranean clover lines was evaluated and all had intermediate to high susceptibility. root galling was negatively correlated with both seed and dry matter yields. soil fumigation significantly reduced the nema ... | 1989 | 19287623 |
| efficacy of fumigant and nonfurmigant nematicides for control of meloidogyne arenaria on peanut. | three tests were conducted to evaluate the efficacy of fumigant and nonfumigant nematicides for control of meloidogyne arenaria race 1 on peanut. methyl bromide, 1,3-d, methyl isothiocyanate, and methyl isothiocyanate mixtures were applied 7 or 8 days preplant either broadcast or in-the-row. aldicarb, ethoprop, fenamiphos, and f5145 were applied at different rates and by different methods at-plant or at early flowering. of the 32 treatments evaluated, only seven resulted in yield increases (p = ... | 1988 | 19290312 |
| soybean-peanut rotations for the management of meloidogyne arenaria. | rotating soybean (glycine max cv. kirby) with peanut (arachis hypogaea cv. florunner) for managing meloidogyne arenaria race 1 was studied for 3 years (1985-87) in a field near headland, alabama. each year soybean plots had lower soil numbers of m. arenaria second-stage juveniles (j2) at peanut harvest than did plots in peanut monocnlture. peanut following either 1 or 2 years of soybean resulted in approximately 50% reduction in j2 soil population densities and a 14% (1-year soybean) or 20% (2-y ... | 1988 | 19290309 |
| soybean response to two isolates of meloidogyne arenaria. | | 1988 | 19290218 |
| response of cowpea breeding lines and cultivars to meloidogyne incognita and m. arenaria. | twenty-four cowpea breeding lines and four cultivars were tested for resistance to meloidogyne incognita in the greenhouse. gall and egg mass ratings indicated a range of responses from susceptible to highly resistant. five breeding lines - vs84-2, vs84-8, vs84-12, vs84-14, and vs84-22 - and the cultivar erectset had gall and egg mass ratings comparable to the m. incognita-resistant cultivar mississippi silver. all of these were also resistant to m. arenaria. significantly fewer m. incognita juv ... | 1987 | 19290274 |
| sterol composition and ecdysteroid content of eggs of the root-knot nematodes meloidogyne incognita and m. arenaria. | free and esterified sterols of eggs of the root-knot nematodes meloidogyne incognita races 2 and 3 and m. arenaria race 1 were isolated and identified by gas-liquid chromatography-mass spectrometry. the major sterols of eggs of each race were 24-ethylcholesterol (33.4-38.8% of total sterol), 24-ethylcholestanol (18.3-25.3%), 24-methylcholesterol (8.6-11.7%), 24-methylcholestanol (7.7-12.5%), and cholesterol (4.6-11.6%). consequently, the major metabolic transformation performed by meloidogyne fe ... | 1987 | 19290155 |
| galling and yields of soybean cultivars grown in meloidogyne arenana-infested soil. | field trials with 39 soybean cultivars and five breeding lines from public and private sources were conducted from 1982 through 1985 at sites infested with meloidogyne arenaria. nematode population densities and root-knot galling were measured for each soybean entry. all were efficient hosts for the nematode, and average juvenile numbers in the soil increased 5-50 x from planting to harvest. differences (p < 0.05) in galling were found among entries in each year. centennial, cobb, coker 368, hut ... | 1987 | 19290135 |
| interrelationships of meloidogyne arenaria and m. incognita on tolerant soybean. | reproduction of meloidogyne arenaria race 2 was excellent on centennial, govan, and kirby soybeans, the latter two of which have tolerance to this species. the m. incognita race 1 isolate reproduced poorly on centennial, especially at the higher of two temperature regimes. numbers of galls and egg masses of m. arenaria plus m. incognita in simultaneous equivalent infestations on centennial did not differ from sequential infestations in which m. arenaria was added first and m. incognita was added ... | 1986 | 19294149 |
| host-parasite relationships of meloidogyne arenaria and m. incognita on susceptible soybean. | pathogenicity and reproduction of single and combined populations of meloidogyne arenaria and m. incognita on a susceptible soybean (glycine max cv. davis) were investigated. significant galling and egg mass production were observed on roots of greenhouse-grown soybean inoculated with m. arenaria and m. incognita, in combination and individually. m. arenaria produced more galls and egg masses than m. incognita, whereas in combined inoculation with both nematode species, gall and egg production w ... | 1985 | 19294112 |
| interaction between meloidogyne arenaria and glomus fascicuqlatus in grape. | root zones of grape (fitis vinifera cv thompson seedless) cuttings were infested with chlamydospores of glomus fasciculatus or eggs of meloidogyne arenaria or both. growth of grapevines was greatest in mycorrhizal (g. fasciculatus) plants. mycorrhizal development and growth of mycorrhizal and nonmycorrhizal plants were reduced in the presence of m. arenaria. at low initial nematode inoculum (pi) levels (approx. 200 eggs/plant), the presence of mycorrhizae enhanced plant growth during 1 yr, but n ... | 1981 | 19300722 |
| quantitative aspects of the development of meloidogyne arenaria larvae in grapevine varieties and rootstocks. | the development and productivity of parasitic stages of meloidogyne arenaria were quantitatively defined in 14 varieties or rootstocks of grapevine. mean development to maturity was related linearly to the number of degree-hours above 10 c temperature experienced from the time of penetration in all cultivars in which nematode adulthood was achieved. averaged across varieties, 13,142 heat units were required for development of the mean individual to maturity. the standard deviation of the develop ... | 1979 | 19305553 |
| polyploidy and parthenogenesis in the root-knot nematode meloidogyne arenaria. | | 1963 | 14079604 |
| characterization of the (gaaa) microsatellite region in the plant parasitic nematode meloidogyne artiellia. | microsatellites have become one of the most powerful genetic markers in biology. we have used dna sequencing to characterize a highly variable microsatellite (gaaa) locus in the root-knot nematode meloidogyne artiellia. the use of microsatellite flanking primers produced four amplification products that are defined as electromorphs, based on conventional length criteria. the sequencing of these four amplification products revealed the presence of new variants in the population due to sequence va ... | 2002 | 12137957 |
| a british root-knot nematode, meloidogyne artiellia n.sp. | | 1961 | 13701441 |
| a new root-knot nematode, meloidogyne baetica n. sp. (nematoda: heteroderidae), parasitizing wild olive in southern spain. | abstract high infection rates of wild olive (olea europaea sp. sylvestris) feeder roots and soil infestation by a new root-knot nematode were found in sandy soil at vejer de la frontera (cádiz), southern spain. morphometric traits and analyses of the nematode esterase electrophoretic pattern as well as of the internal transcribed spacer 1 (its1)-5.8s gene and d2-d3 fragment of the 28s gene of rdna showed that specimens differed clearly from known root-knot nematodes. studies of host-parasite rel ... | 2003 | 18944092 |
| an early record of meloidogyne fallax from ireland. | root-knot nematodes, meloidogyne spp., cause huge economic losses worldwide. currently, three meloidogyne spp. are present on the quarantine a2 list of eppo, meloidogyne chitwoodi, meloidogyne fallax and meloidogyne enterolobii. as a quarantine organism, meloidogyne fallax has been detected in england and northern ireland on sport turf in 2011, and in england on leek in 2013. however, its presence in ireland has probably been overlooked since 1965, when mr. john f. moore and dr. mary t. franklin ... | 2017 | 28144174 |
| bioactivity of ruta graveolens and satureja montana essential oils on solanum tuberosum hairy roots and solanum tuberosum hairy roots with meloidogyne chitwoodi co-cultures. | as a nematotoxics screening biotechnological system, solanum tuberosum hairy roots (sthr) and s. tuberosum hairy roots with meloidogyne chitwoodi co-cultures (sthr/crkn) were evaluated, with and without the addition of the essential oils (eos) of satureja montana and ruta graveolens. eos nematotoxic and phytotoxic effects were followed weekly by evaluating nematode population density in the co-cultures as well as growth and volatile profiles of both in vitro cultures types. growth, measured by t ... | 2016 | 27653470 |
| calcium is involved in the r mc1 (blb)-mediated hypersensitive response against meloidogyne chitwoodi in potato. | functional characterization of the columbia root-knot nematode resistance gene r mc1 ( blb ) in potato revealed the r gene-mediated resistance is dependent on a hypersensitive response and involves calcium. the resistance (r) gene r mc1(blb) confers resistance against the plant-parasitic nematode, meloidogyne chitwoodi. avirulent and virulent nematodes were used to functionally characterize the r mc1(blb)-mediated resistance mechanism in potato (solanum tuberosum). histological observations indi ... | 2015 | 25315813 |
| mitochondrial genomes of meloidogyne chitwoodi and m. incognita (nematoda: tylenchina): comparative analysis, gene order and phylogenetic relationships with other nematodes. | root-knot nematodes (meloidogyne spp.) are among the most important plant pathogens. in this study, the mitochondrial (mt) genomes of the root-knot nematodes, m. chitwoodi and m. incognita were sequenced. pcr analyses suggest that both mt genomes are circular, with an estimated size of 19.7 and 18.6-19.1kb, respectively. the mt genomes each contain a large non-coding region with tandem repeats and the control region. the mt gene arrangement of m. chitwoodi and m. incognita is unlike that of othe ... | 2014 | 24751670 |
| site-specific management of meloidogyne chitwoodi in idaho potatoes using 1,3-dichloropropene; approach, experiences, and economics. | fumigation for nematode management in irrigated potato production systems of idaho is widely practiced. soil injection is the only labeled application method for 1,3-dichloropropene that is conventionally applied on a whole-field basis. plant-parasitic nematode species exhibit spatially variable population densities that provide an opportunity to practice site-specific fumigation to reduce chemical usage and production costs. during 2002 to 2008, 62 fields intended for commercial potato producti ... | 2013 | 24115785 |
| specific diagnosis of two root-knot nematodes, meloidogyne chitwoodi and m. fallax, with satellite dna probes. | abstract meloidogyne chitwoodi and m. fallax are serious pests of potato, and both species have been recently designated as quarantine organisms in the european community and in canada. the sympatric and less damaging species m. hapla is often found associated with both of them under temperate climates. here, we describe the use of satellite dna (satdna) sequences previously isolated from these three root-knot nematode species for the development of specific diagnostic procedures. in dot-blot ex ... | 1999 | 18944750 |
| mining the secretome of the root-knot nematode meloidogyne chitwoodi for candidate parasitism genes. | parasite proteins secreted at the interface of nematode and host are believed to play an essential role in parasitism. here, we present an efficient pipeline of bio-informatic algorithms and laboratory experiments to identify candidate parasitism genes within nematode secretomes, i.e. the repertoire of secreted proteins in an organism. we performed our approach on 12 218 expressed sequence tags (ests) originating from three life stages of the plant parasitic nematode meloidogyne chitwoodi--a mol ... | 2008 | 18705879 |
| control of meloidogyne chitwoodi in potato with fumigant and nonfumigant nematicides. | during 1993-94, several fumigant and nonfumigant nematicides were tested alone and in combination at various rates for control of columbia root-knot nematode (meloidogyne chitwoodi) in potato. ethoprop, oxamyl, or metam sodium alone did not adequately reduce tuber infection. metam sodium plus ethoprop reduced culled tubers to 3%, and metam sodium plus 2 or 3 foliar applications of oxamyl reduced culls to </=10% in all but one instance. fosthiazate provided excellent control of tuber infection wi ... | 2000 | 19271010 |
| a pathotype system to describe intraspecific variation in pathogenicity of meloidogyne chitwoodi. | tests of eight dutch meloidogyne chitwoodi isolates to the differential set for host races 1 and 2 in m. chitwoodi provided no evidence for the existence of host race 2 in the netherlands. the data showed deviations from expected reactions on the differential hosts, which raised doubts of the usefulness of the host race classification in m. chitwoodi. the term ''pathotype'' is proposed for groups of isolates of one meloidogyne sp. that exhibit the same level of pathogenicity on genotypes of one ... | 1999 | 19270911 |
| genetic analysis of resistance to meloidogyne chitwoodi introgressed from solanum hougasii into cultivated potato. | an accession of solanum hougasii, a wild tuber-bearing potato species native to mexico, was found to be resistant to races 1 and 2 of meloidogyne chitwoodi. a resistant selection was selfed and its progeny possessed the same combined resistance uniformly. a selected resistant seedling from the selfed progeny was crossed to cultivated tetraploid potato (s. tuberosum) to form an f hybrid, and was backcrossed to cultivated tetraploid potato to form a bc population in which resistance to the two rac ... | 1999 | 19270896 |
| unusual and strongly structured sequence variation in a complex satellite dna family from the nematode meloidogyne chitwoodi. | an alui satellite dna family has been isolated in the genome of the root-knot nematode meloidogyne chitwoodi. this repeated sequence was shown to be present at approximately 11,400 copies per haploid genome, and represents about 3.5% of the total genomic dna. nineteen monomers were cloned and sequenced. their length ranged from 142 to 180 bp, and their a + t content was high (from 65.7 to 79.1%), with frequent runs of as and ts. an unexpected heterogeneity in primary structure was observed betwe ... | 1998 | 9452524 |
| reproduction of meloidogyne chitwoodi on popcorn cultivars. | popcorn cultivars were evaluated in field and greenhouse tests for resistance to the columbia root-knot nematode, meloidogyne chitwoodi, as potential resistant crops in potato rotations. a nematode reproductive factor (rf) was calculated for each cultivar. reproductive factor values also were compared on a relative basis as percentages of the rf on a susceptible field corn standard, pioneer 3578. popcorn cultivars w206 and robust 33-77 consistently supported low population densities of m. chitwo ... | 1997 | 19274265 |
| effect of the mi gene in tomato on reproductive factors of meloidogyne chitwoodi and m. hapla. | the effect of the mi gene on the reproductive factor of meloidogyne chitwoodi and m. hapla, major nematode pests of potato, was measured on nearly isogenic tomato lines differing in presence or absence of the mi gene. the mi allele controlled resistance to reproduction of race 1 of m. chitwoodi and to one of two isolates of race 2. no resistance to race 3 of m. chitwoodi or to m. hapla was found. variability in response to isolates of race 2 may reflect diversity of virulence genotypes heretofor ... | 1997 | 19274176 |
| resistance of auto- and allotetraploid triticeae species and accessions to meloidogyne chitwoodi based on genome composition. | the columbia root-knot nematode meloidogyne chitwoodi parasitizes several plant species, including grasses that have been developed for semiarid environments, and substantially reduces the productivity of cereals and the longevity of perennial grasses growing under semiarid conditions throughout the intermountain region. thirty-two auto- and allotetraploid (2n = 28) taxa in the perennial triticeae were evaluated as possible sources of resistance to m. chitwoodi. low levels of root galling were o ... | 1997 | 19274138 |
| a pcr assay to identify and distinguish single juveniles of meloidogyne hapla and m. chitwoodi. | random amplified polymorphic dna (rapd) bands that distinguish meloidogyne hapla and m. chitwoodi from each other, and from other root-knot nematode species, were identified using a series of random octamer primers. the species-specific amplified dna fragments were cloned and sequenced, and then the sequences were used to design 20-mer primer pairs that specifically amplified a dna fragment from each species. using the primer pairs, successful amplifications from single juveniles were readily at ... | 1997 | 19274128 |
| host suitability of twelve leguminosae species to populations of meloidogyne hapla and m. chitwoodi. | legumes of the genera astragalus (milkvetch), coronilla (crownvetch), lathyrus (pea vine), lotus (birdsfoot trefoil), medicago (alfalfa), melilotus (clover), trifolium (clover), and vicia (common vetch) were inoculated with a population of melaidogyne chitwoodi from utah or with one of three m. hapla populations from california, utah, and wyoming.thirty-nine percent to 86% of alfalfa (m. scutellata) and 10% to 55% of red clover (t. pratense) plants survived inoculation with the nematode populati ... | 1996 | 19277158 |
| characterization of resistance in a somatic hybrid of solanum bulbocastanum and s. tuberosum, to meloidogyne chitwoodi. | a somatic hybrid, cbp-233, between resistant solanum bulbocastanum (sb-22) and susceptible s. tuberosum (r4) was tested for resistance to meloidogyne chitwoodi race 1. one week after inoculation, only 0.04-0.4% of the initial inoculum (pi, 5,000 eggs) as second stage-juveniles infected sb-22 and cbp-233 root systems, compared to 2% in r4. after 8 weeks, the number of m. chitwoodi in sb-22 and cbp-233 roots remained lower (0.3-1.5% of pi) compared to r4, which increased from 2% to ca. 27%. develo ... | 1995 | 19277265 |
| resistance of diploid triticeae species and accessions to the columbia root-knot nematode, meloidogyne chitwoodi. | the columbia root-knot nematode, meloidogyne chitwoodi race 2, is associated with several plant species, including members of the tribe triticeae. we evaluated 15 diploid species for m. chitwoodi gall and reproductive indices from the following genera: agropyron, pseudoroegneria, hordeum, psathyrostachys, and thinopyrum. species from the genus thinopyrum (thinopyrum bessarabicum; j genome) and psathyrostachys (psathyrostachys fragilis, p. juncea, p. stoloniformis; n genome) expressed more resist ... | 1994 | 19279939 |
| competition between the plant-parasitic nematodes pratylenchus neglectus and meloidogyne chitwoodi. | in experiments on competition between pratylenchus neglectus and meloidogyne chitwoodi in barley, the species that parasitized the roots first inhibited penetration by the latter species. prior presence of p. neglectus impeded the development of m. chitwoodi. pratylenchus neglectus reduced egg production, final population levels, and reproductive index of m. chitwoodi. the reduction was linearly related to initial population densities of p. neglectus. initial population densities of m. chitwoodi ... | 1994 | 19279894 |
| influence of temperature on the virulence of two races of meloidogyne chitwoodi on wheat and barley. | races of the columbia root-knot nematode, meloidogyne chitzooodi, from idaho (r1) and utah (r2) suppressed (p < 0.05) tillering of dusty winter wheat, fielder spring wheat, luther winter barley, and steptoe spring barley at 15-30 c. nematode inoculum density was negatively correlated with tillering (r = -0.79). inoculum densities of both nematode races were negatively correlated with heads per plant (r = -0.83), head length (r = -0.87), and head dry weight (r = 0.73) of fielder spring wheat and ... | 1993 | 19279794 |
| suppression of meloidogyne chitwoodi with sudangrass cultivars as green manure. | meloidogyne chitwoodi race 1 reproduced on piper sudangrass (sorghum bicolor (l.) moench), 332 (sudangrass hybrid), and p855f and p877f (sorghum-sudangrass hybrids), but failed to reproduce efficiently on trudan 8, trudex 9 (sudangrass hybrids), and sordan 79, ss-222, and bravo ii (sorghum-sudangrass hybrids). meloidogyne chitwoodi race 2 behaved similarly and reproduced more efficiently on piper, p855f, and p877f than on trudan 8, trudex 9, or sordan 79. the mean reproductive factor for m. chit ... | 1993 | 19279773 |
| efficacy of ethoprop on meloidogyne hapla and m. chitwoodi and enhanced biodegradation in soil. | responses of egg masses, free eggs, and second-stage juveniles (j2) ofmeloidogyne hapla and m. chitwoodi to ethoprop were evaluated. the results indicated that j2 were the most sensitive, followed by free eggs and egg masses. in general, m. chitwoodi was more susceptible to ethoprop than m. hapla. ethoprop at 7.2 mug a.i./g soil protected tomato roots from upward migrating m. chitwoodi for 5 weeks. the zone of protection was extended to 10 and 20 cm below the root zone when 3.6 and 7.2 cm water ... | 1991 | 19283141 |
| population dynamics of meloidogyne chitwoodi on russet burbank potatoes in relation to degree-day accumulation. | population dynamics of meloidogyne chitwoodi were studied for 2 years in a commercial potato field and microplots. annual second-stage juvenile (j2) densities peaked at harvest in mid-fall, declined through the winter, and were lowest in early summer. in the field and in one microplot study, population increase displayed trimodal patterns during the 1984 and 1985 seasons. overwintering nematodes produced egg masses on roots by 600-800 degree-days base 5 c (dd) after planting. second-generation a ... | 1991 | 19283128 |
| suppression of root-knot nematode populations with selected rapeseed cultivars as green manure. | meloidogyne chitwoodi races 1 and 2 and m. hapla reproduced on 12 cultivars of brassica napus and two cultivars of b. campestris. the mean reproductive factors (rf), rf = pf at 55 days / 5,000, for the three nematodes were 8.3, 2.2, and 14.3, respectively. all three nematodes reproduced more efficiently (p < 0.05) on b. campestris than on b. napus. amending m. chitwoodi-infested soil in plastic bags with chopped shoots of jupiter rapeseed reduced the nematode population more (p < 0.05) than amen ... | 1991 | 19283108 |
| seasonal migration of meloidogyne chitwoodi and its role in potato production. | seasonal vertical migration of meloidogyne chitwoodi through soil and its impact on potato production in washington and oregon was studied. nematode eggs and second-stage juveniles (j2) were placed at various depths (0-180 cm) in tubes filled with soil and buried vertically or in holes dug in potato fields. tubes were removed at intervals over a 12-month period and soil was bioassayed on tomato roots. upward migration began in the spring after water had percolated through the tubes. nematodes we ... | 1991 | 19283107 |
| comparison of fumigant and nonfumigant nematicides for control of meloidogyne chitwoodi on potato. | the fumigant 1,3-dichloropropene (1,3-d) effectively controlled meloidogyne chitwoodi on russet burbank potato, solanum tuberosum. there was a maximum of 4% infected and galled tubers from the 1,3-d treatment after 2,028 degree-days with a base temperature of 5 c (dd5). this compared to 66% infected and galled tubers in aldicarb at-plant treated plots. soil temperature, as determined by dd5, and timing of chemical applications affected the nematicidal activity on m. chitwoodi (p < 0.05). aldicar ... | 1989 | 19287664 |
| resistance in triticum and aegilops spp. to meloidogyne chitwoodi. | two lines of aegilops squarrosa (g 3489 and g 1279) and triticum cultivars anza, cocorit, produra, chinese spring, nugaines, and a synthetic hexaploid were screened for resistance to meloidogyne chitwoodi. reproduction of m. chitwoodi, expressed as eggs per gram root, was low (p < 0.01) on g 3489 and the synthetic hexaploid. reproduction on all other cultivars tested was high although differences (p < 0.01) existed among them. | 1989 | 19287662 |
| pathological reaction of crested wheatgrass cultivars to four meloidogyne chitwoodi populations. | meloidogyne chitwoodi populations from tulelake, california; ft. hall, idaho; beryl, utah; and prosser, washington, significantly (p < 0.05) reduced dry shoot weights of crested wheatgrass (agropyron cristatum l., gaertn. and a. desertorum, fisch. ex link, schult.) cultivars hycrest, fairway, and nordan in experiments conducted in a greenhouse and growth chamber. shoot growth depression, root galling, and nematode reproduction indices were greatest (p < 0.05) on plants inoculated with 5,000 eggs ... | 1989 | 19287637 |
| host-parasite relationship of carrot cultivars and meloidogyne chitwoodi races and m. hapla. | most of the 15 carrot cultivars tested were moderate to good hosts to meloidogyne chitwoodi race 1, whereas all except orlando gold were nonhosts or poor hosts for m. chitwoodi race 2. all carrot cultivars were good hosts for m. hapla. the plant weights of the carrot cultivars red cored chantenay and orlando gold infected with either race of m. chitwoodi were significantly less than uninoculated checks in pots. under field microplot conditions, however, detrimental effects on quality were rarely ... | 1988 | 19290254 |
| host tests to differentiate meloidogyne chitwoodi races 1 and 2 and m. hapla. | the reproductive factor (r = final egg density at 55 days / 5,000, initial egg density) of meloidogyne chitwoodi race 2 (alfalfa race) on 46 crop cultivars ranged from 0 to 130. the reproductive efficiency of m. chitwoodi race 1 (non-alfalfa race) and m. chitwoodi race 2 was compared on selected crop cultivars. the basic difference between the two races lay in their differential reproduction on thor alfalfa and red cored chantenay carrot. m. chitwoodi race 2 reproduced on alfalfa but not on carr ... | 1988 | 19290239 |
| differential response of thor alfalfa to meloidogyne chitwoodi races and m. hapla. | second-stage juveniles (j2) of races 1 and 2 of meloidogyne chiiwoodi and m. hapla readily penetrated roots of thor alfalfa and columbian tomato seedlings; however, few individuals of m. chitwoodi race 1 were able to establish feeding sites and mature on alfalfa. histopathological studies indicate that j2 of race 1 either failed to initiate feeding sites or they caused cell enlargement without typical cell wall thickening. the protoplasm of these cells coagulated, and juveniles of race 1 did not ... | 1988 | 19290231 |
| vertical migration of meloidogyne chitwoodi and m. hapla under controlled temperature. | migratory ability of second-stage juveniles (j2) of two meloidogyne chitwoodi races and a m. hapla population were compared in soil-filled columns at 12, 18, and 24 c. j2 of all populations migrated farthest at 18 c and least at 12 c. nematode survival was significantly reduced (p = 0.05) at 24 c.m. chitwoodi j2 migrated further and in greater numbers than m. hapla j2 at all temperatures. a comparison with and without a host plant demonstrated no preferential migration toward the plant. water pe ... | 1987 | 19290123 |
| host-parasite relationship of meloidogyne chitwoodi on potato. | the soil fumigant 1,3-dichloropropene gave good to excellent control of the columbia root-knot nematode, meloidogyne chitwoodi, on potato, solanum tuberosum l. nonfumigant nematicides (aldicarb, fensulfothion, carbofuran, ethoprop, and phenamiphos) were less effective in controlling m. chitwoodi, since the nematode affects tuber quality more than quantity. soil temperature during the growing season affected parasitism of m. chitwoodi on potato more than did the initial nematode population. there ... | 1985 | 19294115 |
| development of meloidogyne chitwoodi on wheat. | postinfection development of meloidogyne chitwoodi from second-stage juveniles (j2) to mature females and egg deposition on 'nugaines' winter wheat required 105, 51, 36, and 21 days at 10, 15, 20, and 25 c. at 25 c, the j2 induced cavities and hyperplasia in the cortex and apical meristem of root tips with hypertrophy of cortical and apical meristem cell nuclei, 2 and 5 days after inoculation. giant cells induced by late j2 were observed in the stele 10 days after inoculation. clusters of egg-la ... | 1985 | 19294100 |
| host suitability and reaction of bean and pea cultivars to meloidogyne chitwoodi and m. hapla. | | 1985 | 19294062 |
| rangeland grasses as hosts of meloidogyne chitwoodi. | | 1984 | 19294047 |
| effect of soil temperature on reproduction of meloidogyne chitwoodi and m. hapla alone and in combination on potato and m. chitwoodi on rotation plants. | meloidogyne chitwoodi developed and reproduced more rapidly than m. hapla in potato roots at 15, 20, or 25 c when both species of nematodes were inoculated simultaneously at 250 or 1,000 juveniles of each. at 30 c significantly more m. hapla than m. chitwoodi females were found at the lower inoculum level after 41 days. more m. chitwoodi than m. hapla juveniles were extracted from soil at 15, 20, and 25 c, but only at the lower inoculum level at 30 c. potato was considered a more suitable host f ... | 1984 | 19294027 |
| influence of meloidogyne chitwoodi and m. hapla on wheat growth. | meloidogyne chitwoodi reduced the growth of winter wheat 'nugaines' directly in relation to nematode density in the greenhouse, the relationship between top dry weight and initial nematode density suggests a tolerance limit of nugaines wheat to m. chitwoodi of between 0.03 and 0.18 eggs/cm(3) of soil; the value for relative minimum plant top weight was 0.45 g and 0.75 g, respectively. growth of wheat in field microplots containing four population densities (0.003, 0.05, 0.75 and 9 eggs/cm(3) soi ... | 1984 | 19295895 |
| effects of temperature and root leachates on embryogenic development and hatching of meloidogyne chitwoodi and m. hapla. | at 20 c the duration of the embryogenic development of meloiclogyne chitwoodi and m. hapla was about 20 days. at 10 c the embryogenic development was 82-84 days for m. chitwoodi and 95-97 days for m. hapla. the effect of distilled water and root leachates of potato cv. russet burbank, tomato cv. columbian, and wheat cv. hyslop on the hatching of eggs of the two root-knot nematode species was investigated at 4, 7, 10, 15, 20, and 25 c (+/- 1 c). cumulative egg taatch was no greater in root leacha ... | 1983 | 19295777 |
| incidence and distinguishing characteristics of meloidogyne chitwoodi and m. hapla in potato from the northwestern united states. | from september 1980 to june 1981, a survey was conducted in the major potato growing regions of northern california, idaho, nevada, oregon. and washington to determine the distribution of meloidogyne chitwoodi and other meloidogyne spp. meloidogyne chitwoodi and m. hapla were the only root-knot nematode species detected parasitizing potato in all the states surveyed. meloidogyne chitwoodi occurred alone in 83% of the samples and m. hapla in 11%, with 6% of all samples containing both species. th ... | 1982 | 19295719 |
| pathogenicity of the columbia root-knot nematode (meloidogyne chitwoodi) on wheat, corn, oat, and barley. | | 1981 | 19300804 |
| description and sem observations of meloidogyne chitwoodi n. sp. (meloidogynidae), a root-knot nematode on potato in the pacific northwest. | meloidogyne chitwoodi n. sp. is described and illustrated from potato (solanum tuberosum) originally collected from quincy, washington, usa. this new species resembles m. hapla, but its perineal pattern is basically round to oval with distinctive and broken, curled, or twisted striae around and above the anal area. the vulva is in a sunken area devoid of striae. vesicles or vesicle-like structures are present in the median bulb of females. the larva tail, being short and blunt with a hyaline tai ... | 1980 | 19300709 |
| response of malpighia emarginata active germplasm bank accessions to meloidogyne enterolobii parasitism. | malpighia emarginata is cultivated in almost all brazil and is considered an important agricultural crop. the root-knot nematode meloidogyne enterolobii has been described as a major threat to this crop, causing great production losses. due to the scarcity of information about the severity of this parasite in m. emarginata plants in brazil, this study investigated m. enterolobii resistance of ten m. emarginata genotypes from the active germplasm bank of universidade federal rural de pernambuco. ... | 2016 | 27819718 |
| development and validation of lna-based quantitative real-time pcr assays for detection and identification of the root-knot nematode meloidogyne enterolobii in complex dna backgrounds. | meloidogyne enterolobii is a quarantine root-knot nematode posing a major threat to agricultural production systems worldwide. it attacks many host plants, including important agricultural crops, ornamentals, and trees. m. enterolobii is a highly virulent and pathogenic root-knot nematode species, able to reproduce on plants resistant to other meloidogyne spp. significant crop damage has been reported in asia, south america, africa, the united states, france, and greenhouses in switzerland. to i ... | 2015 | 25775103 |
| on the species status of the root-knot nematode meloidogyne mayaguensis rammah & hirschmann, 1988. | holo- and paratypes of the root-knot nematodes meloidogyne mayaguensis rammah & hirschmann, 1988 and meloidogyne enterolobii yang & eisenback, 1983 were morphometrically and morphologically compared. all observed female, male and second-stage juvenile morphometrical and morphological characters are identical for the two studied species. additionally, contradictions between the original species descriptions were unravelled.the present study of holo- and paratypes confirms the taxonomical status o ... | 2012 | 22539912 |
| effects of the mi-1 and the n root-knot nematode-resistance gene on infection and reproduction of meloidogyne enterolobii on tomato and pepper cultivars. | meloidogyne enterolobii is widely considered to be an aggressive root-knot nematode species that is able to reproduce on root-knot nematode-resistant tomato and pepper cultivars. in greenhouse experiments, m. enterolobii isolates 1 and 2 from switzerland were able to reproduce on tomato cultivars carrying the mi-1 resistance gene as well as an n-carrying pepper cultivar. reproduction factors (rf) ranged between 12 and 109 depending on the plant cultivar, with m. enterolobii isolate 2 being more ... | 2009 | 22661786 |
| activity of chalcones derived from 2,4,5-trimethoxybenzaldehyde against meloidogyne exigua and in silico interaction of one chalcone with a putative caffeic acid 3-o-methyltransferase from meloidogyne incognita. | meloidogyne exigua is a parasitic nematode of plants that causes great losses to coffee farmers. in an effort to develop parasitic controls, 154 chalcones were synthesized and screened for activity against this nematode. the best results were obtained with (2e)-1-(4'-nitrophenyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (6) with a 50% lethal concentration (lc50) of 171 μg/ml against m. exigua second-stage juveniles, in comparison to the commercially-available nematicide carbofuran which had an ... | 2013 | 24140596 |
| molecular characterization of fmrfamide-like peptides in meloidogyne graminicola and analysis of their knockdown effect on nematode infectivity. | the rice root-knot nematode, meloidogyne graminicola, seriously impairs the growth and yield of rice which is an important staple food worldwide. the disruption of neuropeptide signalling leading to attenuation in nematode behaviour and thereby perturbed infection, offers an attractive alternative to control nematodes. in this direction, the present study was aimed at mining of putative fmrfamide-like peptides (flps) from the transcriptomic dataset of m. graminicola followed by characterization ... | 2017 | 28366833 |
| transcriptomic and histological responses of african rice (oryza glaberrima) to meloidogyne graminicola provide new insights into root-knot nematode resistance in monocots. | the root-knot nematode meloidogyne graminicola is responsible for production losses in rice ( oryza sativa ) in asia and latin america. the accession tog5681 of african rice, o. glaberrima , presents improved resistance to several biotic and abiotic factors, including nematodes. the aim of this study was to assess the cytological and molecular mechanisms underlying nematode resistance in this accession. | 2017 | 28334204 |
| below-ground attack by the root knot nematode meloidogyne graminicola predisposes rice to blast disease. | magnaporthe oryzae (rice blast) and the root-knot nematode meloidogyne graminicola are causing two of the most important pathogenic diseases jeopardizing rice production. here, we show that root-knot nematode infestation on rice roots leads to important above-ground changes in plant immunity gene expression, which is correlated with significantly enhanced susceptibility to blast disease. a detailed metabolic analysis of oxidative stress responses and hormonal balances demonstrates that the above ... | 2017 | 28151048 |
| interactions between the oomycete pythium arrhenomanes and the rice root-knot nematode meloidogyne graminicola in aerobic asian rice varieties. | aerobic rice fields are frequently infested by pathogenic oomycetes (pythium spp.) and the rice root-knot nematode meloidogyne graminicola. here, the interaction between pythium arrhenomanes and meloidogyne graminicola was studied in rice roots of two aerobic rice varieties. in different experimental set-ups and infection regimes, plant growth, rice yield, pythium colonization, as well as establishment, development and reproduction of m. graminicola were studied. | 2016 | 27473143 |
| thiamine-induced priming against root-knot nematode infection in rice involves lignification and hydrogen peroxide generation. | thiamine (vitamin b1, vb1) can act as a plant defence trigger, or priming agent, leading to a rapid counterattack on pathogen invasion. in this study, the priming effect of thiamine on rice (oryza sativa cv. nipponbare) and its activity against root-knot nematode (meloidogyne graminicola) infection were evaluated. thiamine treatment and subsequent nematode inoculation activated hydrogen peroxide (h2o2) accumulation and lignin deposition in plant roots, and this correlated with enhanced transcrip ... | 2016 | 27103216 |
| comparing the defence-related gene expression changes upon root-knot nematode attack in susceptible versus resistant cultivars of rice. | rice is one of the major staple food crops in the world and an excellent model system for studying monocotyledonous plants. diseases caused by nematodes in rice are well documented and among them, root-knot nematode (rkn), meloidogyne graminicola, causes extensive yield decline. it is therefore necessary to identify novel sources of natural resistance to rkn in rice and to investigate the rice-rkn interaction in detail to understand the basal plant defence mechanisms and nematode manipulation of ... | 2016 | 26961568 |
| meloidogyne graminicola: a major threat to rice agriculture. | superkingdom eukaryota; kingdom metazoa; phylum nematoda; class chromadorea; order tylenchida; suborder tylenchina; infraorder tylenchomorpha; superfamily tylenchoidea; family meloidogynidae; subfamily meloidogyninae; genus meloidogyne. | 2017 | 26950515 |
| a genome-wide association study of a global rice panel reveals resistance in oryza sativa to root-knot nematodes. | the root-knot nematode meloidogyne graminicola is one of the most serious nematode pests worldwide and represents a major constraint on rice production. while variation in the susceptibility of asian rice (oryza sativa) exists, so far no strong and reliable resistance has been reported. quantitative trait loci for partial resistance have been reported but no underlying genes have been tagged or cloned. here, 332 accessions of the rice diversity panel 1 were assessed for gall formation, revealing ... | 2016 | 26552884 |
| biochar-amended potting medium reduces the susceptibility of rice to root-knot nematode infections. | biochar is a solid coproduct of biomass pyrolysis, and soil amended with biochar has been shown to enhance the productivity of various crops and induce systemic plant resistance to fungal pathogens. the aim of this study was to explore the ability of wood biochar to induce resistance to the root-knot nematode (rkn) meloidogyne graminicola in rice (oryza sativa cv. nipponbare) and examine its histochemical and molecular impact on plant defense mechanisms. | 2015 | 26537003 |
| intraspecific variability of the facultative meiotic parthenogenetic root-knot nematode (meloidogyne graminicola) from rice fields in vietnam. | twenty years ago, the facultative meiotic parthenogenetic root-knot nematode (rkn), meloidogyne graminicola, was recognised as an important rice pathogen in south vietnam. although this country is one of the most important rice exporters worldwide, a comprehensive picture of the occurrence of m. graminicola in vietnamese rice fields is still not available. therefore a nematode survey was carried out with the aim of better understanding the geographical distribution, and the pathogenic and geneti ... | 2015 | 26026576 |
| the role of thionins in rice defence against root pathogens. | thionins are antimicrobial peptides that are involved in plant defence. here, we present an in-depth analysis of the role of rice thionin genes in defence responses against two root pathogens: the root-knot nematode meloidogyne graminicola and the oomycete pythium graminicola. the expression of rice thionin genes was observed to be differentially regulated by defence-related hormones, whereas all analysed genes were consistently down-regulated in m. graminicola-induced galls, at least until 7 da ... | 2015 | 25676661 |
| β-aminobutyric acid-induced resistance against root-knot nematodes in rice is based on increased basal defense. | the nonprotein amino acid β-aminobutyric acid (baba) is known to protect plants against various pathogens. the mode of action is relatively diverse and specific in different plant-pathogen systems. to extend the analysis of the mode of action of baba to plant-parasitic nematodes in monocot plants, we evaluated the effect of baba against the root-knot nematode (rkn) meloidogyne graminicola in rice. baba treatment of rice plants inhibited nematode penetration and resulted in delayed nematode and g ... | 2015 | 25608179 |
| fast assembly of the mitochondrial genome of a plant parasitic nematode (meloidogyne graminicola) using next generation sequencing. | little is known about the variations of nematode mitogenomes (mtdna). sequencing a complete mtdna using a pcr approach remains a challenge due to frequent genome reorganizations and low sequence similarities between divergent nematode lineages. here, a genome skimming approach based on hiseq sequencing (shotgun) was used to assemble de novo the first complete mtdna sequence of a root-knot nematode (meloidogyne graminicola). an at-rich genome (84.3%) of 20,030 bp was obtained with a mean sequenci ... | 2014 | 24841955 |
| transcriptional analysis through rna sequencing of giant cells induced by meloidogyne graminicola in rice roots. | one of the reasons for the progressive yield decline observed in aerobic rice production is the rapid build-up of populations of the rice root knot nematode meloidogyne graminicola. these nematodes induce specialized feeding cells inside root tissue, called giant cells. by injecting effectors in and sipping metabolites out of these cells, they reprogramme normal cell development and deprive the plant of its nutrients. in this research we have studied the transcriptome of giant cells in rice, aft ... | 2013 | 23881398 |
| identification of neuropeptides, flp-1 and flp-12 targeting neuromuscular system of rice root knot nematode (rrkn) meloidogyne graminicola. | root-knot nematodes (rkns), meloidogyne spp, are found in all temperate and tropical areas, and are among the most damaging plant pathogens worldwide. m. graminincola is an economically important root parasite on upland, lowland and deepwater rice. fmrfamide-like peptides (flps) play significant role as neurotransmitters or neuromodulators in the nervous system and proposed as one of the important targets for the plant parasitic nematode management. therefore, for the first time, we have cloned ... | 2013 | 23520432 |
| brassinosteroids suppress rice defense against root-knot nematodes through antagonism with the jasmonate pathway. | the importance of phytohormone balance is increasingly recognized as central to the outcome of plant-pathogen interactions. next to their well-known developmental role, brassinosteroids (br) were recently found to be involved in plant innate immunity. in this study, we examined the role of br in rice (oryza sativa) innate immunity during infection with the root-knot nematode meloidogyne graminicola, and we studied the inter-relationship with the jasmonate (ja) pathway. exogenous epibrassinolide ... | 2013 | 23194343 |
| rapid, simple and direct detection of meloidogyne hapla from infected root galls using loop-mediated isothermal amplification combined with fta technology. | the northern root-knot nematode (meloidogyne hapla) is a damaging nematode that has caused serious economic losses worldwide. in the present study, a sensitive, simple and rapid method was developed for detection of m. hapla in infested plant roots by combining a flinders technology associates (fta) card with loop-mediated isothermal amplification (lamp). the specific primers of lamp were designed based on the distinction of internal transcribed spacer (its) sequences between m. hapla and other ... | 2017 | 28368036 |
| identification of two meloidogyne hapla genes and an investigation of their roles in the plant-nematode interaction. | root-knot nematodes are soil-borne pathogens that invade and establish feeding sites in plant roots. they have an extremely broad host range, including most vascular plants. during infection of a susceptible host, root-knot nematodes secrete molecules called effectors that help them establish an intimate interaction with the plant and, at the same time, allow them to evade or suppress plant immune responses. despite the fact that meloidogyne hapla is a significant pest on several food crops, no ... | 2017 | 28301312 |
| assessing attraction of nematodes to host roots using pluronic gel medium. | nematodes and other organisms perceive and respond to plant root exudates. these exudates are affected by the condition and genetic makeup of the plant. attraction of the root-knot nematode meloidogyne hapla to roots is altered in plants with mutations affecting ethylene signaling, suggesting that the root exudates to which the nematode responds are modulated by ethylene signaling. nematode interactions with roots have been difficult to observe directly due to the opaqueness of soil. a medium ba ... | 2017 | 28293853 |
| impact of grapevine (vitis vinifera) varieties on reproduction of the northern root-knot nematode (meloidogyne hapla). | one of the most commonly encountered plant-parasitic nematodes in eastern washington vitis vinifera vineyards is meloidogyne hapla; however, limited research exists on the impact of this nematode on v. vinifera. the objectives of this research were to determine the impact of m. hapla on chardonnay and cabernet sauvignon vine establishment and to determine the host status of v. vinifera varieties/clones predominantly grown in washington to m. hapla. in a microplot experiment, chardonnay and caber ... | 2015 | 26170476 |
| first report of northern root-knot nematode, meloidogyne hapla, parasitic on oaks, quercus brantii and q. infectoria in iran. | root-knot nematodes (rkn) are the most serious plant parasitic nematodes having a broad host range exceeding 2,000 plant species. quercus brantii lindl. and q. infectoria oliv are the most important woody species of zagros forests in west of iran where favors sub-mediterranean climate. national botanical garden of iran (nbgi) is scheduled to be the basic center for research and education of botany in iran. this garden, located in west of tehran, was established in 1968 with an area of about 150 ... | 2015 | 25861121 |
| evaluation of 31 potential biofumigant brassicaceous plants as hosts for three meloiodogyne species. | brassicaceous cover crops can be used for biofumigation after soil incorporation of the mowed crop. this strategy can be used to manage root-knot nematodes (meloidogyne spp.), but the fact that many of these crops are host to root-knot nematodes can result in an undesired nematode population increase during the cultivation of the cover crop. to avoid this, cover crop cultivars that are poor or nonhosts should be selected. in this study, the host status of 31 plants in the family brassicaceae for ... | 2014 | 25276003 |
| segregation and mapping in the root-knot nematode meloidogyne hapla of quantitatively inherited traits affecting parasitism. | the root-knot nematode meloidogyne hapla can reproduce on a wide range of crop species but there is variability in host range and pathogenicity both within and between isolates. the inbred strain vw9 causes galling but does not reproduce on solanum bulbocastanum clone sb22 whereas strain vw8 causes little galling and reproduces poorly on this host. comparison of reproduction on sb22 of nematode f2 lines generated from hybrids between strains vw8 and vw9 revealed that, whereas over half the lines ... | 2013 | 23758293 |
| a gene encoding a peptide with similarity to the plant ida signaling peptide (atida) is expressed most abundantly in the root-knot nematode (meloidogyne incognita) soon after root infection. | small peptides play important roles in intercellular signaling. inflorescence deficient in abscission (ida) is an arabidopsis mutant that does not abscise (shed) its flower petals. the ida gene encodes a small, secreted peptide that putatively binds to two redundant receptor-like kinases (haesa and haesa-like2) that initiate a signal transduction pathway. we identified ida-like (idl) genes in the genomic sequence for meloidogyne incognita and meloidogyne hapla. no orthologous sequences were foun ... | 2013 | 23538028 |
| the 8d05 parasitism gene of meloidogyne incognita is required for successful infection of host roots. | parasitism genes encode effector proteins that are secreted through the stylet of root-knot nematodes to dramatically modify selected plant cells into giant-cells for feeding. the mi8d05 parasitism gene previously identified was confirmed to encode a novel protein of 382 amino acids that had only one database homolog identified on contig 2374 within the meloidogyne hapla genome. mi8d05 expression peaked in m. incognita parasitic second-stage juveniles within host roots and its encoded protein wa ... | 2013 | 23294405 |
| a sequence-anchored linkage map of the plant-parasitic nematode meloidogyne hapla reveals exceptionally high genome-wide recombination. | root-knot nematodes (meloidogyne spp.) cause major yield losses to many of the world's crops, but efforts to understand how these pests recognize and interact with their hosts have been hampered by a lack of genetic resources. starting with progeny of a cross between inbred strains (vw8 and vw9) of meloidogyne hapla that differed in host range and behavioral traits, we exploited the novel, facultative meiotic parthenogenic reproductive mode of this species to produce a genetic linkage map. molec ... | 2012 | 22870404 |
| ethylene signaling pathway modulates attractiveness of host roots to the root-knot nematode meloidogyne hapla. | infective juveniles of the root-knot nematode meloidogyne hapla are attracted to the zone of elongation of roots where they invade the host but little is known about what directs the nematode to this region of the root. we found that arabidopsis roots exposed to an ethylene (et)-synthesis inhibitor attracted significantly more nematodes than control roots and that et-overproducing mutants were less attractive. arabidopsis seedlings with et-insensitive mutations were generally more attractive whe ... | 2013 | 22712507 |
| root-knot nematodes exhibit strain-specific clumping behavior that is inherited as a simple genetic trait. | root-knot nematodes are obligate parasites of a wide range of plant species and can feed only on the cytoplasm of living plant cells. in the absence of a suitable plant host, infective juveniles of strain vw9 of the northern root-knot nematode, meloidogyne hapla, when dispersed in pluronic f-127 gel, aggregate into tight, spherical clumps containing thousands of worms. aggregation or clumping behavior has been observed in diverse genera in the phylum nematoda spanning free-living species such as ... | 2010 | 21151553 |
| determination of preferred ph for root-knot nematode aggregation using pluronic f-127 gel. | root-knot nematodes (meloidogyne spp.) are obligate endoparasites of a wide range of plant species. the infective stage is attracted strongly to and enters host roots at the zone of elongation, but the compounds responsible for this attraction have not been identified. we developed a simple assay to investigate nematode response to chemical gradients that uses pluronic f-127, a synthetic block copolymer that, as a 23% aqueous solution, forms a liquid at low temperature and a gel at room temperat ... | 2009 | 19838866 |
| the genomes of root-knot nematodes. | plant-parasitic nematodes are the most destructive group of plant pathogens worldwide and are extremely challenging to control. the recent completion of two root-knot nematode genomes opens the way for a comparative genomics approach to elucidate the success of these parasites. sequencing revealed that meloidogyne hapla, a diploid that reproduces by facultative, meiotic parthenogenesis, encodes approximately 14,200 genes in a compact, 54 mpb genome. indeed, this is the smallest metazoan genome c ... | 2009 | 19400640 |
| meiotic parthenogenesis in a root-knot nematode results in rapid genomic homozygosity. | many isolates of the plant-parasitic nematode meloidogyne hapla reproduce by facultative meiotic parthenogenesis. sexual crosses can occur, but, in the absence of males, the diploid state appears to be restored by reuniting sister chromosomes of a single meiosis. we have crossed inbred strains of m. hapla that differ in dna markers and produced hybrids and f(2) lines. here we show that heterozygous m. hapla females, upon parthenogenetic reproduction, produce progeny that segregate 1:1 for the pr ... | 2007 | 17483427 |