Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| nematocidal activity to pratylenchus penetrans by culture fluids from actinomycetes and bacteria. | 1966 | 5951708 | |
| effects of nematicides on pratylenchus penetrans, soil nitrification, and growth of flue-cured tobacco | 1996 | 8875840 | |
| alfalfa (medicago sativa l.) resistance to the root-lesion nematode, pratylenchus penetrans: defense-response gene mrna and isoflavonoid phytoalexin levels in roots. | alfalfa (medicago sativa) varieties with antibiosis-based resistance to the root-lesion nematode (pratylenchus penetrans), a migratory endoparasite of many crops, have been developed by recurrent selection. individual plants from these varieties that support significantly lower nematode reproduction were identified for molecular and biochemical characterization of defense responses. before nematode infection, rna blot analysis revealed 1.3-1.8-fold higher phenylpropanoid pathway mrna levels in r ... | 1998 | 9869406 |
| diagnostic probes targeting the major sperm protein gene that may be useful in the molecular identification of nematodes. | discrimination of closely related nematode species is typically problematic when traditional identification characteristics are prone to intraspecific variation. in this study, a molecular approach that can distinguish pratylenchus penetrans and p. scribneri is described. the approach uses universal primers in conjunction with polymerase chain reaction (pcr) to amplify equivalent fragments of the major sperm protein (msp) gene from any nematode. this gene fragment typically includes an intron of ... | 1996 | 11542511 |
| host suitability of arable and vegetable crops for pratylenchus penetrans. | a method was developed to test host suitability for the rootlesion nematode, p. penetrans in pot-experiments. quarts-sand with transplanted seedlings was inoculated with a suspension of p. penetrans in varying stages. it was demonstrated that in a greenhouse at 20 degrees c, a period of six weeks is enough for one generation to develop. after this period root material is separated from the soil and put in a mystifier where nematodes leave the roots. the root material should be held in the mystif ... | 2001 | 12425086 |
| comparison of extraction techniques and augers of different size. | because of differences in winter survival of pratylenchus penetrans after different host plants, concern arose about traditional extraction and soil sampling techniques. possible bottlenecks are a too short incubation period of the root material for the time of year, or an auger size to small to pick up tough, fresh, root material. two experiments were carried out to compare different auger sizes and variations on the standard oostenbrink elutriation technique with additional filter-incubation o ... | 2002 | 12696438 |
| betagamma-dehydrocurvularin and related compounds as nematicides of pratylenchus penetrans from the fungus aspergillus sp. | the new nematicidal compound, betagamma-dehydrocurvularin (1), together with three known compounds, alphabeta-dehydrocurvularin (2), 8-beta-hydroxy-7-oxocurvularin (3) and 7-oxocurvularin (4), were isolated from the culture filtrate and mycelial mats of aspergillus sp. the structures of 1-4 were established by spectroscopic methods including 2d nmr. the biological activities of 1-4 were examined by bioassays with root-lesion nematodes, and lettuce and rice seedlings. | 2003 | 12843675 |
| penipratynolene, a novel nematicide from penicillium bilaiae chalabuda. | new acetylenic nematicidal compound, penipratynolene (1), methy (2'r)-4-(2'-hydroxy-3'-butynoxy)benzoate, together with two known compounds, 6-methoxycarbonylpicolinic acid (2) and 2,6-pyridinedicarboxylic acid (3), were isolated from the culture filtrate of penicillium bilaiae chalabuda. the structures of 1-3 were established by spectroscopic methods. the absolute configuration of 1 was confirmed by using a modified version of mosher's method. compounds 1-3 showed nematicidal activity of 77%, 5 ... | 2004 | 14745197 |
| a survey of sl1-spliced transcripts from the root-lesion nematode pratylenchus penetrans. | plant-parasitic nematodes are important and cosmopolitan pathogens of crops. here, we describe the generation and analysis of 1928 expressed sequence tags (ests) of a splice-leader 1 (sl1) library from mixed life stages of the root-lesion nematode pratylenchus penetrans. the ests were grouped into 420 clusters and classified by function using the gene ontology (go) hierarchy and the kyoto kegg database. approximately 80% of all translated clusters show homology to caenorhabditis elegans proteins ... | 2004 | 15338281 |
| mechanism of control of root-feeding nematodes by mycorrhizal fungi in the dune grass ammophila arenaria. | root-feeding herbivores can affect plant performance and the composition of natural plant communities, but there is little information about the mechanisms that control root herbivores in natural systems. this study explores the interactions between the pioneer dune grass ammophila arenaria, arbuscular mycorrhizal fungi (amf) and the root-feeding nematode pratylenchus penetrans. our objectives were to determine whether amf can suppress nematode infection and reproduction and to explore the mecha ... | 2006 | 16441763 |
| nematicidal activity of 5-hydroxymethyl-2-furoic acid against plant-parasitic nematodes. | a nematicide, 5-hydroxymethyl-2-furoic acid (1), was isolated from cultures of the fungus aspergillus sp. and its structure was identified by spectroscopic analysis. compound 1 showed effective nematicidal activities against the pine wood nematode bursaphelenchus xylophilus and the free-living nematode caenorhabditis elegans without inhibitory activity against plant growth, but 1 did not show any effective nematicidal activity against pratylenchus penetrans. | 2007 | 17542490 |
| fumiquinones a and b, nematicidal quinones produced by aspergillus fumigatus. | new nematicides named fumiquinones a (1) and b (2), together with spinulosin (3), ll-s490beta (4), and pseurotin a (5), were isolated from aspergillus fumigatus and their structures were established by spectroscopic methods including 2d-nmr. compound 1 showed effective nematicidal activities against bursaphelenchus xylophilus and pratylenchus penetrans without inhibiting plant growth except for lettuce seedlings. compound 2 showed effective nematicidal activity against b. xylophilus, but had no ... | 2007 | 17617730 |
| suppression of specific apple root pathogens by brassica napus seed meal amendment regardless of glucosinolate content. | abstract the impact of brassica napus seed meal on the microbial complex that incites apple replant disease was evaluated in greenhouse trials. regardless of glucosinolate content, seed meal amendment at a rate of 0.1% (vol/vol) significantly enhanced growth of apple and suppressed apple root infection by rhizoctonia spp. and pratylenchus penetrans. high glucosinolate b. napus cv. dwarf essex seed meal amendments did not consistently suppress soil populations of pythium spp. or apple root infect ... | 2001 | 18942997 |
| expression of oryzacystatin i and ii in alfalfa increases resistance to the root-lesion nematode. | abstract digestive cysteine proteinases have been isolated from plant-parasitic nematodes as well as coleopteran and hemipteran insects. phytocystatins, inhibitors of cysteine proteinases, are found in a number of plants where they may play a role in defense against pathogens and pests. the cdnas of the phytocystatins from rice, oryzacystatin i (oc-i) and oryzacystatin ii (oc-ii), were expressed in alfalfa (medicago sativa) plants under the control of the potato protease inhibitor ii (pinii) pro ... | 2003 | 18943160 |
| cultural management of microbial community structure to enhance growth of apple in replant soils. | abstract apple replant disease typically is managed through pre-plant application of broad-spectrum soil fumigants including methyl bromide. the impending loss or restricted use of soil fumigants and the needs of an expanding organic tree fruit industry necessitate the development of alternative control measures. the microbial community resident in a wheat field soil was shown to suppress components of the microbial complex that incites apple replant disease. pseudomonas putida was the primary f ... | 2002 | 18943894 |
| vertical distribution of the plant-parasitic nematode, pratylenchus penetrans, under four field crops. | abstract the vertical distribution of pratylenchus penetrans was monitored in four fields cropped with maize, black salsify, carrot, or potato. soil samples were collected at 21-day intervals from may 2002 until april 2003 from five plots (2 x 5 m(2)) per field. per plot, 15 cores were taken to a depth of 70 cm and split into seven segments of 10 cm each. within the plots, segments from corresponding depths were pooled. after mixing, 200-g subsamples were taken and nematodes were extracted by zo ... | 2006 | 18944436 |
| elucidation of the microbial complex having a causal role in the development of apple replant disease in washington. | abstract systematic studies were conducted to elucidate the role of different soil microbial groups in the development of apple replant disease. populations of targeted microorganisms were reduced by the application of semiselective biocides and soil pasteurization. bacteria were not implicated in the disease, because application of the antibiotic chloramphenicol reduced soil populations of bacteria but failed to improve growth of apple transplants, while enhanced growth was achieved at pasteuri ... | 1998 | 18944871 |
| synergism of pratylenchus penetrans and verticillium dahliae manifested by reduced gas exchange in potato. | abstract the effects of solitary and concurrent infection by pratylenchus pene-trans and verticillium dahliae on gas exchange of russet burbank potato (solanum tuberosum) were studied in growth chamber experiments. treatments were p. penetrans at low, medium, and high density; v. dahliae alone at one initial density; the combination of the nematode at these three densities and v. dahliae; and a noninfested control. gas exchange parameters of leaf cohorts of different ages in the different treatm ... | 1997 | 18945123 |
| disease progress based on effects of verticillium dahliae and pratylenchus penetrans on gas exchange in russet burbank potato. | abstract the interactive effects of concomitant infection by the nematode pratylenchus penetrans and the fungus verticillium dahliae on symptom expression in russet burbank potato was studied in growth chamber experiments. treatments were p. penetrans at three initial densities, v. dahliae at one inoculum density, the combination of the nematode at these three densities and the fungus, and a noninfested control. gas exchange was measured nondestructively in leaf cohorts of different ages, one to ... | 1997 | 18945124 |
| nematicidal activities of acetylene compounds from coreopsis lanceolata l. | 1-phenylhepta-1,3,5-triyne (1), 5-phenyl-2-(1'-propynyl)-thiophene (2), and 2-(3'-acetoxy-1'-propynyl)-5-phenylthiophene (3) were isolated from coreopsis lanceolata l., and their structures identified by spectroscopic methods. compounds 1 and 2 showed effective nematicidal activities against bursaphelenchus xylophilus and caenorhabditis elegans, but had hardly any effect against pratylenchus penetrans. compound 3 did not show any effective nematicidal activity. | 2008 | 19227832 |
| decomposers and root feeders interactively affect plant defence in sinapis alba. | aboveground herbivory is well known to change plant growth and defence. in contrast, effects of soil organisms, acting alone or in concert, on allocation patterns are less well understood. we investigated separate and combined effects of the endogeic earthworm species aporrectodea caliginosa and the root feeding nematode species pratylenchus penetrans and meloidogyne incognita on plant responses including growth and defence metabolite concentrations in leaves of white mustard, sinapis alba. soil ... | 2009 | 19252930 |
| influence of lysobacter enzymogenes strain c3 on nematodes. | chitinolytic microflora may contribute to biological control of plant-parasitic nematodes by causing decreased egg viability through degradation of egg shells. here, the influence of lysobacter enzymogenes strain c3 on caenorhabditis elegans, heterodera schachtii, meloidogyne javanica, pratylenchus penetrans, and aphelenchoides fragariae is described. exposure of c. elegans to l. enzymogenes strain c3 on agar resulted in almost complete elimination of egg production and death of 94% of hatched j ... | 2006 | 19259452 |
| management of lesion nematodes and potato early dying with rotation crops. | soil-incorporated rotation/green manure crops were evaluated for management of potato early dying caused by verticillium dahliae and pratylenchus penetrans. after two years of rotation/green manure and a subsequent potato crop, p. penetrans numbers were less after 'saia' oat/'polynema' marigold, 'triple s' sorghum-sudangrass, or 'garry' oat than 'superior' potato or 'humus' rapeseed. the area under the disease progress curve (audpc) for early dying was lowest after saia oat/marigold, and tuber y ... | 2006 | 19259461 |
| reproduction of pratylenchus penetrans on 24 common weeds in potato fields in québec. | twenty-four weeds commonly found in commercial potato fields in quebec were evaluated for their host suitability to the root-lesion nematode, pratylenchus penetrans, under greenhouse conditions. brown mustard (brassica juncea) and rye (secale cereale) were included as susceptible controls and forage pearl millet hyb. cfpm 101 (pennisetum glaucum) as a poor host. pratylenchus penetrans multiplied well on 22 of the 24 weed species tested (pf/pi >/= rye or brown mustard). cirsium arvense, leucanthe ... | 2007 | 19259506 |
| mortality of pratylenchus penetrans by volatile fatty acids from liquid hog manure. | as part of our research program assessing the use of liquid hog manure (lhm) to control root-lesion nematodes, pratylenchus penetrans, a series of acute toxicity tests was conducted to: (i) examine if non-ionized forms of volatile fatty acids (vfa) are responsible for the mortality of p. penetrans exposed to lhm under acidic conditions, (ii) determine if caenorhabditis elegans can be a surrogate for p. penetrans in screening tests by comparing their sensitivities to vfa, (iii) characterize the n ... | 2008 | 19259528 |
| effect of compost and manure soil amendments on nematodes and on yields of potato and barley: a 7-year study. | a 7-year study located in prince edward island, canada, examined the influence of compost and manure on crop yield and nematode populations. the compost used in this study consisted of cull waste potatoes, sawdust, and beef manure in a 3:3:1 ratio, respectively. no plant-parasitic nematodes were detected in samples collected from windrow compost piles at 5- and 30-cm depths prior to application on field plots. low population densities of bacterial-feeding nematodes were recovered from compost wi ... | 2003 | 19262763 |
| management options for pratylenchus penetrans in easter lily. | alternatives to reduce or modify nematicide use for minimizing groundwater contamination in easter lily were explored in two field trials. alternatives to standard 1,3-dichloropropene (1,3-d) plus phorate injection in the first trial were: (i) delaying applications until after winter rains, (ii) removing roots from planting stock, (iii) 1,3-d via drip irrigation, (iv) a chitin-urea soil amendment, (v) the registered insecticide disulfoton, and (vi) several nonregistered nematicides. none of the ... | 2003 | 19262778 |
| generalized linear dynamics of a plant-parasitic nematode population and the economic evaluation of crop rotations. | in 1-year experiments, the final population density of nematodes is usually modeled as a function of initial density. often, estimation of the parameters is precarious because nematode measurements, although laborious and expensive, are imprecise and the range in initial densities may be small. the estimation procedure can be improved by using orthogonal regression with a parameter for initial density on each experimental unit. in multi-year experiments parameters of a dynamic model can be estim ... | 2005 | 19262843 |
| effect of forage and grain pearl millet on pratylenchus penetrans and potato yields in quebec. | rotation crop experiments were conducted from 1998 to 2000 to assess the impact of forage and grain pearl millet (pennisetum glaucum) on pratylenchus penetrans populations in three potato (solanum tuberosum cv. superior) fields in quebec. these crops were compared to oats and(or) barley. forage millet had a suppressive effect on p. penetrans populations after a 1 year rotation. the following year, marketable potato yields were negatively correlated with initial p. penetrans densities on two expe ... | 2005 | 19262846 |
| comparison of pratylenchus penetrans infection and maladera castanea feeding on strawberry root rot. | the interaction of lesion nematodes, black root rot disease caused by rhizoctonia fragariae, and root damage caused by feeding of the scarab larva, maladera castanea, was determined in greenhouse studies. averaged over all experiments after 12 weeks, root weight was reduced 13% by r. fragariae and 20% by m. castanea. the percentage of the root system affected by root rot was increased by inoculation with either r. fragariae (35% more disease) or p. penetrans (50% more disease) but was unaffected ... | 2005 | 19262852 |
| impacts of sustained use of dairy manure slurry and fertilizers on populations of pratylenchus penetrans under tall fescue. | various manures and composts have been reported to reduce population densities of plant-parasitic nematodes. dairy manure slurry is often used as a primary source of nitrogen for forage crops. this study was conducted to determine the effects of dairy manure on population densities of pratylenchus penetrans parasitizing tall fescue. beginning in 1994, dairy manure and inorganic fertilizer were applied after each harvest (2 to 4 times/year) at rates of 50 and 100 kg nh-n/ha; control plots were no ... | 2005 | 19262862 |
| nematicides increase grain yields in spring wheat cultivars and suppress plant-parasitic and bacterial-feeding nematodes. | grain yields of spring wheat (triticum aestivum l. cvs. ac barrie, ac walton, ac wilmot, belvedere, glenlea) in field plots over a 3-year period were increased (p < 0.001) by an average of 0.56 (25.1%) and 1.17 (52.5%) tonnes/ha in comparison to untreated check plots when aldicarb at 2.24 kg or fosthiazate at 13.5 a.i./ha, respectively, were broadcast and incorporated into the soil to suppress nematodes. the planned f test using orthogonal coefficients indicated that the mean response of grain y ... | 2005 | 19262893 |
| suppression of pratylenchus penetrans populations in potato and tomato using african marigolds. | current strategies for management of pratylenchus penetrans in both white potato and tomato consist of the use of fumigant or non-fumigant nematicides or crop rotation. the objective of this study was to determine if double-cropping african marigolds (tagetes erecta) with potatoes or tomatoes could reduce p. penetrans populations. plots were 10 m x 3 m arranged in a randomized complete block design with four replications. treatments included marigolds, potatoes or tomatoes, and natural weedy fal ... | 2002 | 19265920 |
| plant pathogen population dynamics in potato fields. | modern technologies incorporating geographic information systems (gis), global positioning systems (gps), remote sensing, and geostatistics provide unique opportunities to advance ecological understanding of pests across a landscape. increased knowledge of the population dynamics of plant pathogens will promote management strategies, such as site-specific management, and cultural practices minimizing the introduction and impact of plant pathogens. the population dynamics of alternaria solani, ve ... | 2002 | 19265932 |
| effect of entomopathogenic nematodes and trichoderma harzianum on the strawberry black root rot pathogens pratylenchus penetrans and rhizoctonia fragariae. | the effects of inundative releases of entomopathogenic steinernema carpocapsae and s. feltiae infective juveniles and applications of the biological control fungus trichoderma harzianum t-22 (rootshield) on pratylenchus penetrans and strawberry black root rot caused by rhizoctonia fragariae were determined in field microplots and small plots. entomopathogenic nematodes were applied as a soil drench at rates of 7.4 or 14.8 billion per ha in may or august for 3 years. rootshield was applied as cro ... | 2002 | 19265955 |
| seasonal populations of pratylenchus penetrans and meloidogyne hapla in strawberry roots. | strawberry roots were sampled through the year to determine the populations and distribution of pratylenchus penetrans and meloidogyne hapla. three strawberry root types were sampled-structural roots; feeder roots without secondary tissues; and suberized, black perennial roots. both lesion and root-knot nematodes primarily infected feeder roots from structural roots or healthy perennial roots. few nematodes were recovered from soil, diseased roots, or suberized roots. lesion nematode recovery wa ... | 2002 | 19265965 |
| competition between heterodera glycines and meloidogyne incognita or pratylenchus penetrans: independent infection rate measurements. | competition on soybean between heterodera glycines (race 3) and meloidogyne incognita or h. glycines and pratylenchus penetrans were investigated in greenhouse experiments. each pair of nematode species was mixed in 3-ml suspensions at ratios of 1,000:0, 750:250, 500:500, 250:750, and 0:1,000 second-stage juveniles or mixed stages for p. penetrans. nematodes from a whole root system were counted and infection rates standardized per 1,000 nematodes (per replication) prior to testing the null hypo ... | 2003 | 19265967 |
| interaction of pratylenchus penetrans and rhizoctonia fragariae in strawberry black root rot. | a split-root technique was used to examine the interaction between pratylenchus penetrans and the cortical root-rotting pathogen rhizoctonia fragariae in strawberry black root rot. plants inoculated with both pathogens on the same half of a split-root crown had greater levels of root rot than plants inoculated separately or with either pathogen alone. isolation of r. fragariae from field-grown roots differed with root type and time of sampling. fungal infection of structural roots was low until ... | 2003 | 19265969 |
| effects of pratylenchus penetrans and rhizoctonia fragariae on vigor and yield of strawberry. | microplot and small field-plot experiments were conducted to determine the effects of pratylenchus penetrans on strawberry yield over several seasons and to evaluate the effects of nematode control on strawberry vigor and yield. pratylenchus penetrans alone or in combination with the black root rot pathogen, rhizoctonia fragariae, reduced strawberry yield in microplots over time. there were no differences in effects on yield among r. fragariae anastomosis groups a, g, or i. the interaction of th ... | 1999 | 19270914 |
| survey of crop losses in response to phytoparasitic nematodes in the united states for 1994. | previous reports of crop losses to plant-parasitic nematodes have relied on published results of survey data based on certain commodities, including tobacco, peanuts, cotton, and soybean. reports on crop-loss assessment by land-grant universities and many commodity groups generally are no longer available, with the exception of the university of georgia, the beltwide cotton conference, and selected groups concerned with soybean. the society of nematologists extension committee contacted extensio ... | 1999 | 19270925 |
| influence of rotation crops on the strawberry pathogens pratylenchus penetrans, meloidogyne hapla, and rhizoctonia fragariae. | field microplot, small plot, and greenhouse experiments were conducted to determine the effects of rotation crops on pratylenchus penetrans, meloidogyne hapla, and rhizoctonia fragariae populations. extraction of p. penetrans from roots and soil in microplots and field plots planted to rotation crops was highest for garry oat, lowest for triple s sorgho-sudangrass and saia oat, and intermediate for strawberry, buckwheat, and canola. isolation of r. fragariae from bait roots was highest for straw ... | 1999 | 19270931 |
| population growth of pratylenchus penetrans on winter cover crops grown in the pacific northwest. | population growth of pratylenchus penetrans on 13 fall and winter cover crops was studied in the greenhouse and field. all crops except oat cv. saia supported population growth of p. penetrans in greenhouse experiments, although the response of p. penetrans to oat cv. saia varied considerably between experiments. the mean ratio of the final population density/initial population density (pf/pi) after 16 weeks for p. penetrans added to a greenhouse soil mix was 0.09, whereas pf/pi values after 10 ... | 2000 | 19270948 |
| pseudomonas chlororaphis strain sm3, bacterial antagonist of pratylenchus penetrans. | the interaction of pseudomonas chlororaphis strain sm3 and the root-lesion nematode pratylenchus penetrans was investigated in three separate greenhouse experiments with soils from southern british columbia, canada. the bacteria were applied to the roots of strawberry plants and planted in unpasteurized field soils, with natural or supplemented infestation of p. penetrans. nematode suppression in roots was evident after 6 or 10 weeks in all experiments. root or shoot growth were increased after ... | 2000 | 19270964 |
| the effect of marigolds (tagetes spp.) and other cover crops on pratylenchus penetrans and on following potato crops. | root-lesion nematodes (primarily pratylenchus penetrans) were monitored in two marigold cultivars (tagetes tenuifolia cv. nemakill and cv. nemanon), annual ryegrass (lolium multiflorum cv. lemtal), red clover (trifolium pratense cv. florex), and soybean (glycine max cv. proteus), and in the following potato (solanum tuberosum cv. superior) crop during three growth sequences. meadow fescue (festuca elatior cv. miner) and bee plant (phacelia tanacetifolia cv. gipha) were added to the trial in the ... | 2000 | 19271006 |
| effect of temperature on pratylenchus penetrans development. | reproduction and development of pratylenchus penetrans were studied on genetically transformed ladino clover roots. solitary females developing on transformed roots in nutrient gellan gum medium (ph 5.5) deposited 1.2, 1.5, 1.6, 1.8, and 2.0 eggs per day at the respective temperatures of 17, 20, 25, 27, and 30 degrees c. the number of eggs deposited was highly correlated with temperature. a reduction in egg-laying rates at the start of hatching was observed at all temperatures. juvenile mortalit ... | 1997 | 19274163 |
| impact of plant nutrition on pratylenchus penetrans infection of prunus avium rootstocks. | a hypothesis that cherry rootstocks grown under optimal nutrient conditions are affected less by pratylenchus penetrans infection than those grown under deficient nutrient conditions was tested by growing four prunus avium l. rootstocks ('mazzard', 'mahaleb', 'gi148-1', and 'gi148-8') at a soil ph of 7.0 over a period of 3 months under greenhouse conditions (25 ñ 2 degrees c). pratylenchus penetrans was inoculated at 0 (control) or 1,500 nematodes per g fresh root weight for a total of 3,600, 4, ... | 1997 | 19274171 |
| pathogenicity of pratylenchus penetrans, heterodera glycines, and meloidogyne incognita on soybean genotypes. | the pathogenicity of heterodera glycines, meloidogyne incognita, and pratylenchus penetrans on h. glycines-resistant 'bryan,' tolerant-susceptible 'g88-20092,' and intolerant-susceptible 'tracy m' soybean cultivars was tested using plants grown in 800 cm(3) of soil in 15-cm-diam. clay pots in three greenhouse experiments. plants were inoculated with 0, 1,000, 3,000, or 9,000 h. glycines race 3 or m. incognita eggs, or vermiform stages of p. penetrans/pot. forty days after inoculation, nmnbers of ... | 1998 | 19274203 |
| effect of initial nematode population density on the interaction of pratylenchus penetrans and verticillium dahliae on 'russet burbank' potato. | four similar growth chamber experiments were conducted to test the hypothesis that the initial population density (pi) of pratylenchus penetrans influences the severity of interactive effects of p. penetrans and verticillium dahliae on shoot growth, photosynthesis, and tuber yield of russet burbank potato. in each experiment, three population densities of p. penetrans with and without concomitant inoculation with v. dahliae were compared with nematode-free controls. the three specific pi of jr p ... | 1998 | 19274204 |
| temporal changes in the vertical distribution of pratylenchus penetrans under raspberry. | population densities of pratylenchus penetrans and the biomass of fine roots of raspberry at depths of 0-5, 5-10, 10-20, and 20-30 cm were determined every 2 weeks for 2 years. the vertical distribution of p. penetrans varied from season to season, but the seasonal changes were not similar for the 2 years. in most seasons, the greatest population density was in the 5 to 10-cm-depth interval. population densities of p. penetrans were not consistently correlated with the vertical distribution of r ... | 1998 | 19274208 |
| the potential of thiarubrine c as a nematicidal agent against plant- parasitic nematodes. | thiarubrine c, a polyacetylenic 1,2-dithiin isolated from the roots of rudbeckia hirta (asteraceae), exhibited strong nematicidal activity in in vitro and growth chamber assays. thiarubrine c was toxic, in the absence of light, to the plant-parasitic nematodes meloidogyne incognita and pratylenchus penetrans at lcs of 12.4 ppm and 23.5 ppm, respectively. a minimum exposure time between 12 and 24 hours was the critical period for nematode mortality due to thiarubrine c. although thiarubrine c was ... | 1998 | 19274210 |
| strawberry cultivars vary in their resistance to northern lesion nematode. | the genetic diversity of commercial cultivars of strawberry fragaria x ananassa from various parentages, as expressed by their resistance to the northem lesion nematode pratylenchus penetrans, was evaluated in nematode-infested field plots for two growing seasons. data taken for each plant in each season included soil nematode pi and pf, end-of-season nematode numbers in each entire root system, and end-of-season fresh and dry top weight and whole root system weight. resistance was estimated usi ... | 1998 | 19274249 |
| problems associated with crop rotation for management of pratylenchus penetrans on easter lily. | in humboldt and del norte counties of california and curry county, oregon, easter lilies (lilium longiflotum) are grown commercially in a 3- to 6-year rotation with pasture for cattle and sheep. bulbs are sold to greenhouse operations to produce flowering plants. the lesion nematode, pratylenchus penetrans, is a serious detriment to easter lily production. both soil and planting stock are often infested; typically, a dual nematicide application is used consisting of a preplant soil fumigation fo ... | 1998 | 19274250 |
| fosthiazate for suppression of pratylenchus penetrans in potato on prince edward island. | the impacts of fosthiazate on potato (solanum tuberosum) tuber yields and populations of root lesion nematodes (primarily pratylenchus penetrans) were studied during 1991-1994 in experimental plots on prince edward island. tuber yields were greater in treated plots when compared to untreated plots by 8% and 30% during 1991 and 1993, respectively. numbers of nematodes in roots were reduced by the treatments in every year, and nematode populations in soil were suppressed in 1991, 1993, and 1994. t ... | 1997 | 19274269 |
| characterization of pratylenchus penetrans from ten geographically isolated populations based on their reaction on potato. | single female cuhures of pratylenchus penetrans were established from soil and root samples collected from 10 geographically isolated locations in north america. the resultant isolates were used to evaluate nematode egression from and multiplication on roots of potato clones to distinguish intraspecific differences among isolates. the 10 nematode isolates were statistically separated into four groups based on percentage of nematodes that egressed from the p. penetrans-resistant potato done l 118 ... | 1996 | 19277170 |
| population dynamics of pratylenchus penetrans, paratylenchus sp., and criconemella xenoplax on western oregon peppermint. | endoparasitic nematode populations are usually measured separately for soil and roots without a determination of the quantitative relation between soil and root population components. in this study, pratylenchus penetrans populations in peppermint soil, roots, and rhizomes were expressed as the density within a standardized core consisting of 500 g dry soil plus the roots and rhizomes contained therein. populations of paratylenchus sp. and criconemella xenoplax in 500 g dry soil were also determ ... | 1996 | 19277174 |
| differentiation of two new york isolates of pratylenchus penetrans based on their reaction on potato. | the behavior of two isolates of pratylenchus penetrans on six potato clones was assessed to test the hypothesis that these nematode isolates from new york were different. four potato cultivars (superior, russet burbank, butte, and hudson) and two breeding lines (ny85 and l118-2) were inoculated with nematode isolates designated cornell (cr) and long island (li). population increase and egression of nematodes from roots were used to distinguish resistance and susceptibility of the potato clones. ... | 1995 | 19277297 |
| impact of multi-year cropping regimes on solanum tuberosum tuber yields in the presence of pratylenchus penetrans and verticillium dahliae. | five cropping regimes involving combinations of 2 legumes, alfalfa (medicago sativa) and yellow sweet dover (melilotus officinalis), 2 monocots, corn (zea mays) and sudax (sorghum halupeuse x sorghum sudanese), and potato (solanum tuberosum cv. superior) were tested for their impact on potato yields in a field infested with pratylenchus penetrans and verticillium dahliae. no differences in 1990 tuber yields were observed among the five cropping regimes (p < 0.05). in 1991, yields following 1 yea ... | 1995 | 19277337 |
| axenizing and culturing endomigratory plant-parasitic nematodes using pluronic f127, including its effects, on population dynamics of pratylenchus penetrans. | a non-chemical technique for surface sterilizing plant-parasitic nematodes for aseptic cultures is described. the method is most applicable to nematodes with active migratory infective stages and requires only a few starting specimens. rate of achieving a primary aseptic culture with the technique ranged from 60%-100% depending on the conditions of the specimens collected for culturing. aseptic cultures of species of meloidogyne, rotylenchuluz, pratylenchus, and radopholus initiated with the met ... | 1996 | 19277353 |
| infection of pratylenchus penetrans by nematode-pathogenic fungi. | eleven fungal isolates were tested in agar dishes for pathogenicity to pratylenchus penetrans. of the fungi that produce adhesive conidia, hirsutella rhossiliensis was a virulent pathogen; verticillium balanoides, drechmeria coniospora, and nematoctonus sp. were weak or nonpathogens. the trapping fungi, arthrobotrys dactyloides, a. oligospora, monacrosporium dlipsosporum, and m. cionopagum, killed most of the p. penetrans adults and juveniles added to the fungus cultures. an isolate of nematocto ... | 1993 | 19279772 |
| comparative response of alfalfa to pratylenchus penetrans populations. | four populations of pratylenchus penetrans did not differ (p > 0.05) in their virulence or reproductive capability on lahontan alfalfa. there was a negative relationship (r = -0 .7 9 ) between plant survival and nematode inocula densities at 26 +/- 3 c in the greenhouse. all plants survived at an inoculum level (pi) of 1 nematode/cm(3) soil, whereas survival rates were 50 to 55% at 20 nematodes/cm(3) soil. alfalfa shoot and root weights were negatively correlated (r = - 0.87; p < 0.05) with nema ... | 1993 | 19279795 |
| resistance in potato to pratylenchus penetrans. | potato clones from five different breeding populations were evaluated for their relative resistance and susceptibility to pratylenchus penetrans. resistance and susceptibility were distinguished by an index of susceptibility (si) calculated from the numbers of p. penetrans (including eggs) per g of root of individual clones in relation to that of a susceptible control at 30 or 70 days after inoculation. evaluations were carried out using 7.5-cm clay pots in a growth chamber at 24 c with 15-hour ... | 1993 | 19279796 |
| correlation of edaphic factors with plant-parasitic nematode population densities in a forage field. | two hundred soil samples from the a(p) horizon of a reed canarygrass field overlaying several different but related soils in northern minnesota were analyzed for plant-parasitic nematodes and 22 edaphic factors. pratylenchus penetrans was the predominant nematode taxon. others were aglenchus agricola, tylenchorhynchus spp., heterodera trifolii, paratylenchus spp., tylenchus maius, and criconemella sp. five nematode taxa, p. penetrans, a, agricola, tylenchorhynchus spp., h. trifolii, and paratyle ... | 1993 | 19279821 |
| management of pratylenchus penetrans on oriental lilies with drip and foliar-applied nematicides. | pratylenchus penetrans is a pest for producers of oriental lilies in northern california. concern over groundwater contamination from 1,2-dichloropropane following shank injections of 1,3-dichloropropene-l,2-dichloropropane mixture and granular applications of aldicarb prompted testing for alternative methods of controlling p. penetrans. in field trials, nematicides applied by drip irrigation (ethoprop, fenamiphos, oxamyl, sodium tetrathiocarbonate, water extracts of marigold and vetch, and 1,3- ... | 1993 | 19279836 |
| occurrence of the clover cyst nematode, heterodera trifolii, in prince edward island soils. | in a survey of potato and rotational crops on prince edward island, canada, the cyst stage of the clover cyst nematode, heterodera trifolii, was found in 43 of 63 sites sampled; however, only 12% of the cysts contained eggs. the root lesion nematode, pratylenchus penetrans, was the dominant plant parasitic nematode and was found in 56 sites. extraction of cysts from soil was similar using either the schuiling centrifuge or the fenwick can method, although the former was more convenient to use. t ... | 1993 | 19279856 |
| interactions among pratylenchus penetrans, p. scribneri, and verticillium dahliae in the potato early dying disease complex. | microplots were infested with combinations of the fungus verticillium dahliae and pratylenchus penetrans and p. scribneri to test for individual and combined effects of these organisms on potato yield and nematode reproduction. verticillium dahliae alone caused yield losses in all 3 years of the experiment, and the interaction between p. penetrans and v. dahliae was significant (p </= 0.05) in 2 years. pratylenchus penetrans alone caused yield losses in 2 years and p. scribneri alone caused yiel ... | 1994 | 19279885 |
| effect of hirsutella rhossiliensis on infection of potato by pratylenchus penetrans. | we evaluated the ability of the nematode-pathogenic fungus hirsutella rhossiliensis (deuteromycotina: hyphomycetes) to reduce root penetration and population increase of pratylenchus penetrans on potato. experiments were conducted at 24 c in a growth chamber. when nematodes were placed on the soil surface 8 cm from a 14-day-old potato cutting, the fungus decreased the number entering roots by 25%. to determine the effect of the fungus on population increase after the nematodes entered roots, we ... | 1994 | 19279896 |
| inheritance of resistance to pratylenchus penetrans in alfalfa. | fifty-two alfalfa (medicago sativa l.) clones, randomly selected from the cultivar baker and the experimental line mngrn-4, were evaluated for resistance (based on nematode reproduction) to pratylenchus penetrans in growth chamber tests (25 c). twenty-five clones, representing the range of nematodes and eggs per plant, were selected and retested. four moderately resistant and two susceptible alfalfa clones were identified. inheritance of resistance to p. penetrans was studied in these six clones ... | 1994 | 19279915 |
| effect of single and interplantings on pathogenicity of pratyenchus penetrans and p. neglectus to alfalfa and crested wheatgrass. | alfalfa is a host of pratylenchus penetrans and p. neglectus, whereas crested wheatgrass is a host of p. neglectus but not of p. penetrans. in a 120-day greenhouse experiment at 24 ñ 3 c, p. neglectus inhibited the growth of 'lahontan' alfalfa and 'fairway' crested wheatgrass. there were no differences in persistence and plant growth of alfalfa and crested wheatgrass, or reproduction of p. neglectus, in single plantings of alfalfa (ao) or crested wheatgrass (cwo), or in interplanted alfalfa and ... | 1994 | 19279916 |
| plant-parasitic nematodes associated with cherry rootstocks in michigan. | in two field trials, 10-year-old sweet and tart cherry rooted on 'mazzard', 'mahaleb', 'mxm 2', 'mxm 14', 'mxm 39', 'mxm 60', 'mxm 97', and 'colt' showed 10-203 pratylenchus penetrans per g fresh root from all tart rootstocks, and up to 46 pratylenchus, criconemella, and xiphinema spp. per 100 cm(3) soil. infestation of soil containing 1-year-old mazzard, mahaleb, mxm 60, 'gi148-1', and 'g1148-8' with 625/100 cm(3) soil of either p. penetrans or c. xenoplax resulting in final nematode population ... | 1994 | 19279962 |
| a plant health care program for brambles in the pacific northwest. | pratylenchus and xiphinema species have been associated with decline and mortality of brambles (rubus species) in the pacific northwest of the united states. these nematodes cause direct feeding damage and (or) transmit viruses that result in poor fruit quality and plant decline. a nematode management program has been developed by the author to minimize chemical use and nematode-induced damage while optimizing fruit production. nematode management is an integral part of a total plant health care ... | 1992 | 19283023 |
| influence of irrigation and heterorhabditis bacteriophora on plant-parasitic nematodes in turf. | daily irrigated, 80% pan replacement, and nonirrigated field plots of kentucky bluegrass (poa pratensis l.) were inoculated with a mixture of steinernema carpocapsae (all strain) and heterorhabditis bacteriophora (hp-88 strain) in 1988. in 1989, daily irrigated and nonirrigated plots were inoculated with hp-88 alone. the turf and associated soil contained populations of tylenchorhynchus dubius, t. nudus, pratylenchus penetrans, paratylenchus projectus, and criconemella rustica. in irrigated plot ... | 1992 | 19283039 |
| effects of fumigant nematicides on yield and quality of paste tomatoes grown in southwestern ontario. | field trials were conducted at the delhi research station, ontario, canada, on a fox loamy sand soil during 1987 and 1988 to evaluate the effects of row application of the fumigants telone ii, telone c-17, vorlex plus, and vorlex plus cp on the yield and quality of paste tomato (lycopersicon esculentum mill. cv. ferry morse 6203). the four fumigants were equally effective in controlling the natural field populations of root lesion nematodes (pratylenchus penetrans cobb). a significant reduction ... | 1992 | 19283042 |
| penetration of celery and alfalfa roots by pratylenchus penetrans as affected by temperature. | a greater percentage of females than juveniles or males of p. penetrans penetrated celery roots grown in infested soil at 5, 18, or 30 c; the difference was greatest at 5 c. the time of initial penetration of alfalfa seedlings inoculated with single nematodes on water agar varied with temperature. females penetrated the seedlings earlier and over a wider range of temperatures than did males or juveniles. the rate of penetration was highest for females. after initial penetration, the penetration ... | 1991 | 19283112 |
| morphological observations of pratylenchus penetrans from celery and strawberry in southern ontario. | pratylenchus penetrans was obtained from premier strawberry in norfolk county and the niagara peninsula and from celery in the latter area. host affected the dimensions of p. penetrans to a greater extent than geographical area in ontario. adults of p. penetrans from southern ontario tended to be smaller than those reported elsewhere. the presence of three lip annules was consistent in the seven populations studied, although in some specimens one of the annules did not entirely encompass the hea ... | 1991 | 19283114 |
| effect of oxamyl treatment of potato seed pieces on pratylenchus penetrans and yield. | in the first 2 years of a 3-year (1987-89) microplot study, aqueous solutions of oxamyl (32 mg/ml) were applied to cut potato (solanum tuberosum cv. russet burbank) tubers, grown in fine sandy loam infested with pratylenchus penetrans. the seed-piece treatment alone and the seed-piece treatment followed by three foliar sprays generally reduced (p = 0.05) population densities of p. penetrans in the soil at midseason and in the soil and roots at harvest, compared to the control. in 1989, all seed ... | 1991 | 19283188 |
| modeling of yield loss in potato early dying caused by pratylenchus penetrans and verticillium dahliae. | yield-loss models were developed for potato early dying, caused by an interaction between verticillium dahliae and pratylenchus penetrans. yield data were collected over 5 years (1985-1989) from potato plants grown in microplots infested with v. dahliae and (or) p. penetrans. the model y = b + (1 - b)/(1 + [vd/36.7]), where y was the relative yield (with uninfested controls = 1.0) and vd was the preplant density of v. dahliae microsclerotia per cm(3) soil, was fitted to the data set. when p. pen ... | 1992 | 19283209 |
| efficacy of oxamyl coated on alfalfa seed with a polymer sticker in pratylenchus and meloidogyne infested soils. | a polymer sticker was used as a coating in which oxamyl was applied to seeds of alfalfa cultivar saranac for the control of pratylenchus penetrans and meloidogyne hapla. the sticker, diluted 1:1 (sticker:water) to 1:5, delayed seedling emergence during the first 4 days after planting. by day 13, however, emergence from all sticker treatments was comparable to the control. shoot growth of seedlings at day 21 was less than that of the control only from seeds coated with a 1:1 dilution; root growth ... | 1989 | 19287603 |
| nematode autofluorescence and its use as an indicator of viability. | representatives of 15 nematode genera were viewed with 450-490-nm epi-illumination and found to autofluoresce. the autofluorescence was limited to 1-5-mum-d globules in the intestinal cells of live nematodes. when adult pratylenchus penetrans or caenorhabditis elegans were killed with formaldehyde, freezing, or heat, autofluorescence dispersed throughout the body. mixed stages of p. penetrans were killed by freezing at several different temperatures. estimates of survival based on autofluorescen ... | 1989 | 19287626 |
| carbamate and organophosphorus nematicides: acetylcholinesterase inhibition and effects on dispersal. | the sensitivities of acetylcholinesterases (ache) from the fungus-feeder aphelenchus avenae and the plant-parasitic species helicotylenchus dihystera and pratylenchus penetrans and the housefly, musca domestica, were compared using a radiometric assay which utilized h(3) acetylcholine as a substrate. nematode ache were generally less sensitive to inhibition by organophosphorns and carbamate pesticides than were ache from the housefly. ache from the plant-parasitic species and a. avenae were gene ... | 1989 | 19287642 |
| effects of pratylenchus penetrans on the infection of strawberry roots by gnomonia comari. | the fungus gnomonia comari, causal agent of strawberry leaf blotch, was inoculated at the crown of young axenized strawberry plants growing in sterilized sand. only the roots were colonized, and the infection was symptomless. when the fungus colonized the roots in the presence of the root lesion nematode pratylenchus penetrans, the plants were extremely stunted and their root system was necrotic. fungal conidiospores were found attached to the cuticle of nematodes extracted from soil inoculated ... | 1989 | 19287646 |
| ultrastructural pathology of cells affected by pratylenchus penetrans in alfalfa roots. | cortical parenchyma cells penetrated and fed upon by pratylenchus penetrans for 48 hours contained only cytoplasmic debris. proximal cells had an increase in tannin deposits, degenerated mitochondria, increased numbers of ribosomes, and no internal membrane structure. often the endodermis was collapsed and contained massive tannin deposits on the inner cell wall and cell lumen. similar observations were made in the stele, except tannin deposits were not as prominent. multivesicnlate structures w ... | 1989 | 19287649 |
| effects of fumigant and nonfumigant nematicides on pratylenchus penetrans and yield of potato. | in 1984-85 metham-sodium and the combination of 1,3-dichloropropene plus aldicarb decreased (p = 0.05) soil population densities of pratylenchus penetrans at planting, midseason, and at harvest relative to the untreated control. these treatments increased (p = 0.05) marketable potato tuber yield from 27% to 46% in 1984 and from 23% to 37% in 1985, as compared with the control. in 1984 oxamyl (10% granular and 24% liquid) applied immediately after planting increased (p = 0.05) only the total yiel ... | 1989 | 19287665 |
| control of pratylenchus penetrans on potato with metam-sodium applied in irrigation water. | in 1986, metam-sodium broadcast at 152, 76, 38, 19, and 9.5 kg a.i./ha suppressed the population density of 19,600 pratylenchus penetrans/kg soil at planting by 100, 90, 63, 23, and 14%, respectively, and in 1987, with 1,370 p. penetrans/kg soil, by 99, 88, 57, 11, and 1%. at harvest, soil population densities increased 2.2-fold in 1986 and 13.9-fold in 1987. rate of population increase was similar at all rates of nematicide except it was slower at 152 kg a.i./ha in 1987. in both years, shoot an ... | 1989 | 19287674 |
| reproduction of pratylenchus penetrans on potato and crops grown in rotation with potato. | the relative suitability of potato and crops frequently grown in rotation with potato as hosts for pratylenchus penetrans was evaluated. suitability of rye, wheat, corn, oat, sorgho-sudangrass, and potato were compared in pot studies based on ratios of final population : initial population density and densities of nematodes in roots at harvest. population densities increased more on potato, oat, and corn than on rye, wheat, and sorgho-sudangrass. there were no differences among the four rye cult ... | 1990 | 19287696 |
| observations on the invasion and endoparasitic behavior of the root lesion nematode pratylenchus penetrans. | the endoparasitic behavior of pratylenchus penetrans was examined using video-enhanced contrast microscopy to observe living nematodes inside root tissue. feeding behavior could be separated into phases of probing, cell penetration by the stytet, salivation, and food ingestion for brief and extended periods. after cell penetration, a small "salivation zone" was formed around the stylet tip. no feeding tubes were observed. feeding and migration were interrupted by rest phases when a nematode beca ... | 1990 | 19287726 |
| differences in egress of male and female pratylenchus penetrans from pea roots. | 1990 | 19287768 | |
| plant-parasitic nematodes in maine agricultural soils. | in a survey of plant-parasitic nematodes associated with agricultural crops in nine maine counties, 744 soil samples from 26 potential host plants were analyzed between november 1987 and january 1989. the most commonly encountered nematode genus was pratylenchus, occurring in 85% of the samples from most crops, except blueberries and onions. pratylenchus penetrans and p. crenatus were found commonly as species mixtures, with p. penetrans composing 40-80% of the mixture. meloidogyne hapla was enc ... | 1990 | 19287791 |
| effects of fenamiphos on pratylenchus penetrans and growth of apple. | a 3-year study was conducted to evaluate fenamiphos at 20.2 kg a.i./ha applied in both fall and spring or in spring only for the control of pratylenchus penetrans on apple, malus domestica cv. granny smith on m7a rootstock. the initial population densities of p. penetrans within the plot area were 89/250 cm(3) soil and 268/g root dry weight. fenamiphos increased (p < 0.05) trunk diameter in years 2 and 3 and shoot length in years 1 and 2. yield data obtained in year 3 showed that the spring only ... | 1990 | 19287796 |
| influence of edaphic factors and previous crop on pratylenchus spp. population densities in potato. | root and soil samples from commercial potato fields were assayed for nematodes in 1983 and 1984. pratylenchus spp. population densities in suffolk county, new york, were consistently, though not always statistically, higher in potato fields that had been planted to rye or wheat rather than potatoes during the previous growing season. regardless of the previous crop, population densities in the two potato production areas in suffolk county differed significantly: population densities on the south ... | 1987 | 19290111 |
| anhydrobiosis in pratylenchus penetrans and tylenchorhynchus n. sp. in cultivated soils cropped to winter rye. | anhydrobiotes of pratylenchus penetrans were found in two cultivated soils sown to rye in southern ontario during the growing season. anhydrobiotes at the 0-2.5-cm depth were recovered from 9 and 6 of 11 samplings, respectively, of a vineland silt loam and a fox loamy sand during the dry summer of 1983. at the 2.5-15.0-cm depth, anhydrobiotes were recovered less frequently. in the summer of 1984, anhydrobiotes of p. penetrans were recovered once and anhydrobiotes of tylenchorhynchus n. sp. twice ... | 1987 | 19290125 |
| pratylenchus penetrans population dynamics on three potato cultivars. | reproduction of pratylenchus penetrans on the potato cultivars hudson, katahdin, and superior was determined in greenhouse and field microplot experiments. although all three cultivars were good hosts for p. penetrans, differences in reproductive rate were found. in one greenhouse experiment, katahdin plants inoculated with 1,500 or 15,000 p. penetrans per pot had larger population densities at harvest than did superior; however differences between these cultivars were not significant in three o ... | 1987 | 19290156 |
| effect of ditylenchus dipsaci and pratylenchus penetrans on verticillium wilt of alfalfa. | verticillium albo-atrum wilt symptoms appeared faster and were significantly more severe in the presence of ditylenchus dipsaci in vernal, a wilt-susceptible cultivar, than in marls kabul, a wilt-resistant cultivar. winter kill in the field was not affected by the nematode during the first winter, but 50% of plants were killed in the second winter. forage yield from nematode-infected plants was significantly reduced the second year. interaction with v. albo-atrum did not significantly reduce for ... | 1987 | 19290158 |
| effects of fumigants and systemic pesticides on pratylenchus penetrans and potato yield. | replicated trials were conducted near alliston, ontario, in 1983 and 1984 to evaluate the efficacy of five chemical treatments in controlling the root-lesion nematode pratylenchus penetrans on potato, solanum tuberosum cv. russet burbank. the fumigants vorlex, at 55 liters product/ha, and telone ii b, at 75 liters product/ha, were more effective in suppressing high initial population densities of 18,320 and 50,880 p. penetrans/kg soil in 1983 and 1984, respectively, than single applications of t ... | 1987 | 19290166 |
| control of pratylenchus penetrans and meloidogyne hapla and yield response of alfalfa due to oxamyl seed treatments. | alfalfa (medicago sativa l. cv. saranac) seed were soaked for 20 minutes in water, acetone, or methanol containing 10 or 50 mg/ml of oxamyl (vydate l) or coated with a 2% aqueous cellulose solution containing the same amounts of oxamyl. seed were analyzed for oxamyl by hplc immediately after treatment and after 9 and 26 months of storage. oxamyl content of alfalfa seed did not decline after 26 months of storage. the effects of seed treatment on growth of alfalfa and nematode control were examine ... | 1987 | 19290170 |
| growth of potato and control of pratylenchus penetrans with oxamyl-treated seed pieces in greenhouse studies. | oxamyl was applied to both uncut and cut potato tubers in aqueous solutions of 1,000 to 32,000 mug/ml. emergence in greenhouse pots was delayed for a day or more after soaking cut tuber pieces in 32,000 mug/ml. after 10 weeks plant growth was greater, relative to the control, when pratylenchus penetrans-infested soil was planted with cut tubers soaked for 20 minutes in 32,000 mug/ml. soaking for 40 minutes did not increase nematode control nor affect plant growth. oxamyl applied to tubers at 1,0 ... | 1988 | 19290230 |
| nematodes associated with potato in prince edward island and new brunswick. | analysis of soil and root samples collected from potato fields across prince edward island and the woodstock-grand falls region of new brunswick, canada showed that pratylenchus spp. were the dominant plant-parasitic nematodes. pratylenchus penetrans occurred more often on prince edward island, and p. crenatus predominated in new brunswick. it was estimated that about 10% of the sites from prince edward island had population levels of pratylenchus spp. that may have caused economic losses. | 1987 | 19290267 |
| relationship of yield and pratylenchus spp. population densities in superior and russet burbank potato. | number of pratylenchus spp. (primarily p. penetrans) were recorded at planting in experimental potato plots over a 9-year period at one location on prince edward island. tuber yields of 'superior' and 'russet burbank' potatoes in plots treated with aldicarb were compared with yields in adjacent untreated plots. there was a linear relationship between the number of root lesion nematodes at planting and tuber yield increases after treatment for superior, but not for russet burbank (p < 0.05). when ... | 1988 | 19290299 |
| joint influence of pratylenchus penetrans (nematoda) and leptinotarsa decemlineata (insecta) on solanum tuberosum productivity and pest population dynamics. | the joint action of a plant parasitic nematode, pratylenchus penetrans (root-lesion nematode), and an insect defoliator, leptinotarsa decemlineata (colorado potato beetle), on growth, development, and yield of solanum tuberosum cv. superior was studied in the field. three population densities of p. penetrans were superimposed on each of three population levels of l. decemlineata. the major impact of p. penetrans on final yield was through a reduction in the number of tubers formed during tuber i ... | 1984 | 19294016 |
| anhydrobiosis in pratylenchus penetrans. | anhydrobiotic survival of pratylenchus penetrans was compared in several soil moisture regimes. bodies of anhydrobiotic nematodes were coiled. in slow-dried soils, vineland silt loam (vsl) and fox loamy sand (fls), 70 and 58% of the total p. penetrans populations were anhydrobiotic when soil moistures reached ca. 3% and water potential 15 kpa or greater. coiling began at a much lower water potential in fls than in vsl. in fast-dried soils, only 31 and 22% of the p. penetrans populations in the s ... | 1984 | 19294023 |
| response of peach seedlings to infection by the root lesion nematode pratylenchus penetrans under controlled conditions. | twenty-one open pollinated populations of peach rootstock seedlings were evaluated for their response to infection by the root lesion nematode, pratylenchus penetrans, over a period of 98 days. nematode-infected peach seedling populations were shorter in plant height and had less shoot weight but more dry root weight than nematode-free controls. rootstock differences were demonstrated for nematode increase over the 98-day period, and average total numbers of nematodes in soil and roots. rootstoc ... | 1984 | 19294029 |