| morphological variability and molecular phylogeny of the nematophagous fungus monacrosporium drechsleri. | an isolate of the nematode-trapping fungus monacrosporium drechsleri was collected from cultures of the root-knot nematode meloidogyne arenaria that had been maintained on tomato roots in greenhouse pots in beltsville, maryland. the plant-parasitic nematodes heterodera glycines, meloidogyne incognita and pratylenchus zeae and the free-living nematodes caenorhabditis elegans and panagrellus redivivus were placed on colonies of m. drechsleri grown in petri dishes to study ability of the isolate to ... | 2005 | 16396348 |
| survey of nematodes on coffee in hawaii. | surveys of coffee fields in hawaii during 1989-1991 indicated the presence of 10 nematode species in 8 genera. after coffee was planted in fields previously in sugarcane, populations of criconemella sp. and pratylenchus zeae gradually decreased, while rotylenchulus reniformis and, in one field, meloidogyne incognita, increased in numbers. coffee is a poor host of r. reniformis, but weeds in coffee plantations may support this nematode. at present, nematodes pose no serious threat to hawaii's exp ... | 1992 | 19283060 |
| nematode problems affecting agriculture in the philippines. | nematodes are considered major pests on most economic crops in the philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. radopholus similis is the most destructive nematode on banana, while meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. tylenchulus semipenetrans is a problem on citrus and rotylenchulus reniformis on pineapple and some legume crops. hirschmanniella oryzae and aphelench ... | 1988 | 19290204 |
| population dynamics of plant nematodes in cultivated soil: effect of sod-based rotations in cecil sandy loam. | in a 6-year study of four nematode species in sod-based corn (zea mays) rotations, population densities varied with different cropping systems. continuous corn, with or without a winter rye (secale cereale) or vetch (vicia villosa) cover, favored an increase of pratylenchus zeae and suppressed trichodorus christiei, helicotylenchus dihystera, and xiphinema americanum. a four-year sod-based rotation (3 years sod, 1 year corn) of 'coastal' bermudagrass (cynodon dactylon) and fescue (festuca arundi ... | 1969 | 19325691 |
| de novo analysis of the transcriptome of pratylenchus zeae to identify transcripts for proteins required for structural integrity, sensation, locomotion and parasitism. | the root lesion nematode pratylenchus zeae, a migratory endoparasite, is an economically important pest of major crop plants (e.g. cereals, sugarcane). it enters host roots, migrates through root tissues and feeds from cortical cells, and defends itself against biotic and abiotic stresses in the soil and in host tissues. we report de novo sequencing of the p. zeae transcriptome using 454 flx, and the identification of putative transcripts encoding proteins required for movement, response to stim ... | 2016 | 26292651 |
| endoparasitic nematodes in maize roots in the western transvaal as related to soil texture and rainfall. | eight endoparasitic nematode species were recovered from 170 maize root samples in western transvaal, republic of south africa. pratylenchus zeae had the highest average population density (17,454/5 g roots), followed by p. neglectus (5,827/5 g roots), p. penetrans (5,617/5 g roots), p. brachyurus (3,060/5 g roots), meloidogyne incognita plus m. javanica (301 juveniles/5 g roots), p. crenatus (130/5 g roots), and rotylenchutus parvus (64/5 g roots). the 17 reasonably homogeneous farming areas (r ... | 1989 | 19287620 |
| distribution of field corn roots and parasitic nematodes in subsoiled and nonsubsoiled soil. | a field trial was conducted for 2 years in an arredondo fine sand containing a tillage pan at 15-20 cm deep to determine the influence of subsoiling on the distribution of corn roots and plant-parasitic nematodes. soil samples were taken at various depths and row positions at 30, 60, and 90 days after planting in field corn subsoiled under the row with two chisels and in non-subsoiled corn. at 30 and 60 days, in-row nematode population densities to 60 cm deep were not affected by subsoiling comp ... | 1986 | 19294167 |
| effects of storage temperature and extraction procedure on recovery of plant-parasitic nematodes from field soils. | storage of nematodes in soil at -15 c for 1 to 16 weeks greatly increased nematode recovery by a sugar-flotation-sieving procedure. one week of exposure to -15 c killed all nematodes except pratylenchus zeae and tylenchorhynchus claytoni which were recoverable in decreasing numbers up to 10 weeks by the baermann funnel method. optimum storage temperature for survival of most nematode species was 13 c. the numbers of meloidogyne incognita, t. claytoni, belonolaimus iongicaudatus, and p. zeae reco ... | 1969 | 19325684 |
| detection and quantification of root-knot nematode (meloidogyne javanica), lesion nematode (pratylenchus zeae) and dagger nematode (xiphinema elongatum) parasites of sugarcane using real-time pcr. | a number of different plant parasitic nematode species are found associated with sugarcane in south africa. of these, the root-knot nematode (meloidogyne javanica), the lesion nematode (pratylenchus zeae) and the dagger nematode (xiphinema elongatum) are potentially the most damaging pests. identification and enumeration of the number of these nematodes are necessary for providing advice to farmers as well as studying the effects of various treatments in field and glasshouse trials. we report on ... | 2008 | 18378423 |
| effect of watering regimen on injury to corn and grain sorghum by pratylenchus species. | the effect of simulated rainfall frequency on the pathogenicity of pratylenchus zeae and p. brachyurus was studied in four greenhouse experiments. corn and grain sorghum were watered at different intervals during predetermined cycles to create a gradient of water-stressed plants. each experiment included nematode and uninoculated treatments. growth reaction of plants to different frequencies of watering was significant but was not affected by the presence of nematodes. pratylenchus zeae numbers ... | 1993 | 19279822 |
| gene silencing in root lesion nematodes (pratylenchus spp.) significantly reduces reproduction in a plant host. | root lesion nematodes (rlns, pratylenchus species) are a group of economically important migratory endoparasitic plant pathogens that attack host roots of major crops such as wheat and sugarcane, and can reduce crop yields by 7-15%. pratylenchus thornei and pratylenchus zeae were treated with double stranded rna (dsrna) to study gene silencing, (rna interference, rnai), as a potential strategy for their control. mixed stages of nematodes of both species ingested dsrna when incubated in a basic s ... | 2013 | 23201220 |
| interpreting upland rice yield and pratylenchus zeae relationships: correspondence analyses. | correspondence analyses were used to explore the relationships between yield and populations of pratylenchus zeae in an upland rice field and in a greenhouse experiment. initial soil (pi) and final root (pf) population densities of p. zeae, and yield (y) of rice cv. upl ri5 were determined at 490 spots in the field. very low y was linked to very high pf. low y was linked to medium or high pi and medium pf. medium to very high y were clustered with undetectable pi and very low or high pf. all yie ... | 1993 | 19279769 |
| host suitability of commercial sunflower hybrids to pratylenchus zeae. | host suitability of commercial sunflower hybrids to pratylenchus zeae was studied in the field and greenhouse. for comparison, one maize and one grain sorghum inbred line, both susceptible to p. zeae, were included in the greenhouse experiments. pratylenchus zeae densities extracted from the roots of sunflower hybrids grown in naturally infested soil were low. in the first greenhouse experiment, p. zeae densities per 5 g roots and per root system were lower (p = 0.05) in four sunflower hybrids t ... | 1989 | 19287672 |
| host status of five weed species and their effects on pratylenchus zeae infestation of maize. | the host suitability of five of the most common weed species occurring in maize (zea mays l.) fields in south africa to pratylenchus zeae was tested. based on the number of nematodes per root unit, mealie crotalaria (crotalaria sphaerocarpa) was a good host; goose grass (eleusine indica), common pigweed (amaranthus hybridus), and thorn apple (datura stramonium) were moderate hosts; and khaki weed (tagetes minuta) was a poor host. only the root residues of khaki weed suppressed the p. zeae infest ... | 1988 | 19290263 |
| seasonal population dynamics of selected plant-parasitic nematodes as measured by three extraction procedures. | seasonal fluctuations in field populations of meloidogyne spp. (m. incognita and m. hapla), pratylenchus zeae, criconemoides ornatum, tylenchorhynchus claytoni, belonolaimus longicaudatus, and helicotylenchus dihystera were determined monthly for 1 year by three extraction procedures. baermann funnel method (bf) gave highest recoveries of meloidogyne spp. and p. zeae during summer and fall, but centrifugal-flotation (cf) and sugar-flotation-sieving (sfs) usually yielded higher numbers of these n ... | 1969 | 19325683 |
| phytoparasitic nematode surveys of arkansas cotton fields, 1986-1988. | surveys from 1986 to 1988 identified 22 phytoparasitic nematode species in arkansas cotton fields. meloidogyne spp. was found in ca. 15% of the fields sampled. of these samples ca. 33% were found to have a population density of 106/100 cm(3) of soil or more. rotylenchulus reniformis was found in high numbers (5,000 +/100 cm(3) of soil) in 1% of the fields sampled in 1988. heterodera glycines was found in ca. 22% of the samples, presumably because of past cropping to soybean. other common species ... | 1989 | 19287659 |
| seasonal population dynamics of selected plant-parasitic nematodes on four monocultured crops. | seasonal fluctuations in field populations of meloidogyne incognita, pratylenchus zeae, p. brachyurus, criconemoides ornatus, trichodorus christiei, and helicotylenchus dihystera on monocultured corn, cotton, peanut, and soybean were determined monthly for 4 yr. population densities of m. incognita were greater in corn and cotton plots than in peanut and soybean plots from july until january. those of pratylenchus spp. were greater on corn and soybean than on cotton and peanut during all months ... | 1974 | 19308120 |
| effects of pratylenchus zeae and quinisulcius acutus alone and in combination on sorghum. | host-parasite relationships of pratylenchus zeae and quinisulcius acutus, alone or in combination, were studied on sorghum in the greenhouse and laboratory. q. acutus at 1,000 or 5,000 nematodes per 15-cm-d pot and p. zeae at 500 nematodes per pot significantly suppressed plant height and fresh and oven dry shoot and root weights. a mixture of 1,000 q. acutus and 500 p. zeae per pot resulted in greatest suppression of growth. roots of plants inoculated with q. acutus alone were reduced in number ... | 1985 | 19294079 |
| influence of organic pesticides on nematode and corn earworm damage and on yield of sweet corn. | soil fumigants and nonvolatile pesticides increased growth and yield of sweet corn 'seneca chief' over that of control plants in a 3-year study. nematicide treatments increased average yields by 31% over controls, but did not significantly affect the mean weight per ear. increase in yield was related to control of belonolaimus longicaudatus, trichodorus christiei and pratylenchus zeae. nonvolatile chemicals more effectively reduced populations of b. longicaudatus and t. christiei than did soil f ... | 1973 | 19319328 |
| nematocidal effects of natural phytoregulators jasmonic acid and methyl-jasmonate against pratylenchus zeae and helicotylenchus spp. | the aim of this study was to evaluate the nematocidal effects of natural phytoregulators jasmonic acid (ja) and methyl-jasmonate (mj) against plant parasitic nematodes pratylenchus zeae (graham) (pratylenchidae) and helicotylenchus spp. (hoplolaimidae). both ja and mj promoted elevated percentages of mortality in p. zeae and helicotylenchus spp. after 12 and 24 h of nematodes exposition at different concentrations of jasmonates. considering the potential use of jasmonates as biofertiliser added ... | 2013 | 22587493 |
| a comparison of low-temperature and ambient-temperature sem for viewing nematode faces. | faces of lesion nematodes pratylenchus teres (populations rtb and jk) and p. zeae or the bacterivore distolabrellus veechi were observed on frozen specimens with low-temperature scanning electron microscopy and as chemically fixed, critical-point dried specimens with conventional scanning electron microscopy. amphidial secretions were preserved in chemically fixed but not cryofixed lesion nematodes. overhanging liplets of chemically fixed d. veechi may be artifactual because they appeared as var ... | 2003 | 19265978 |
| grain yield and heterosis of maize hybrids under nematode infested and nematicide treated conditions. | plant-parasitic nematodes are present on maize but resistant genotypes have not been identified in uganda. this study was aimed at determining the level of nematode resistance among f(1) hybrids, and to estimate grain yield, heterosis and yield losses associated with maize hybrids under nematode infestation. the 30 f(1) hybrids and two local checks were evaluated in a split plot design with nematode treatment (nematode infested versus nematicide treated) as the whole plot factor, and the hybrids ... | 2011 | 23429435 |