| 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 |
| pasteuria sp. parasitizing trophonema okamotoi in florida. | two populations of trophonema okamotoi parasitized by pasteuria sp. were found on liquidambar styraciflua (sweetgum) and on an unidentified tropical grass in north-central florida. endospores of this pasteuria sp. attached to motile vermiform second-stage juveniles (j2) and males of t. okamotoi, but not to other developmental stages. sporangia and new endospores were produced only inside the bodies of swollen and sedentary third- and fourth-stage juveniles and females that developed in the host ... | 1992 | 19283199 |
| expression of resistance in peanuts to pratylenchus brachyurus: impact on screening for resistance. | | 1984 | 19294049 |
| occurrence of pasteuria-like organisms on selected plant-pamsitic nematodes of pineapple in the hawaiian islands. | soils from 320 sites representing diverse undisturbed habitats from five hawaiian islands were assessed for occurrence of pasteuria-like organisms. mean annual rainfall at sites ranged from 125-350 cm, elevation from 69-2,286 m, and annual mean temperature from 12-24 c. seven different natural communities were represented: wet lowland, mesic lowland, wet montane, mesk montane, dry montane, mesic subalpine, and dry alpine. pasteuria spp. in a soil sample was detected by baiting with infective sta ... | 1995 | 19277305 |
| effects of pratylenchus brachyurus and p. coffeae on seedlings of coffea arabica. | two experiments were carried out to evaluate the effects of pratylenchus brachyurus and p. coffeae on coffea arabica. the first experiment was conducted in a greenhouse to determine the effects of pratylenchus brachyurus and p. coffeae on seedlings of coffea arabica cv. mundo novo. both pratylenchus spp. reduced the growth of coffee seedlings. higher contents of soluble sugars were detected in the leaves of infected plants. the reproduction rate of p. brachyurus was very low on cv. mundo novo, i ... | 1998 | 19274229 |
| crop yields and nematode population densities in triticale-cotton and triticale-soybean rotations. | triticale cv. beagle 82, cotton cv. mcnair 235, and soybean cv. twiggs were arranged in three cropping sequences to determine the effects of fenamiphos and cropping sequence on nematode population densities and crop yields under conservation tillage for 4 years. the cropping sequences were triticale (t)-cotton (c)-t-c, t-soybean (s)-t-s, and t-c-t-s. numbers of meloidogyne incognita second-stage juveniles declined on trificale but increased on cotton and soybean each year. root-gall indices of c ... | 1998 | 19274228 |
| intraspecific morphological variation among populations of pratylenchus brachyurus and p. coffeae. | three populations of pratylenchus coffeae and two of p. brachyurus, each originating from a single female, were maintained on citrus spp. or solanum nigrum l. for several years under greenhouse conditions. nematodes were extracted from roots, and adult female specimens were killed, fixed, and mounted in glycerine for microscopic study. variables measured were distance between vulva and anus and lengths of the stylet, posterior uterine sac, and tail. the mean data and coefficients of variability ... | 1978 | 19305830 |
| phenotypic and molecular analysis of a pasteuria strain parasitic to the sting nematode. | pasteuria strain s-1 was found to parasitize the sting nematode belonolaimus longicaudatus. s-1 spores attached to several strains of b. longicaudatus from different geographical locations within the united states. however, they did not adhere to any of the following species: heterodera schachtii, longidorus africanus, meloidogyne hapla, m. incognita, m. javanica, pratylenchus brachyurus, p. scribneri, p. neglectus, p. penetrans, p. thornei, p. vulnus, and xiphinema spp. the 16s rrna genes from ... | 2001 | 19266005 |
| correlations of field populations of nematodes with crop growth responses for determining relative involvement of species. | treated and nontreated field plots were assayed, and the population density of each plant-parasitic nematode present was compared with crop growth and yield and with the population densities of other nematode species in the same plots. the strongest correlations between nematode population densities and growth responses occurred when soil assays for nematodes were made 55-73 days after planting. belonolairnus longicaudatus was the most damaging parasite on peanut, arachis hypogaea, as evidenced ... | 1975 | 19308153 |
| reproduction of belonolaimus longicaudatus, meloidogyne javanica, paratrichodorus minor, and pratylenchus brachyurus on pearl millet (pennisetum glaucum). | pearl millet (pennisetum glaucum) has potential as a grain crop for dryland crop production in the southeastern united states. whether or not pearl millet will be compatible in rotation with cotton (gossypium hirsutum), corn (zea mays), and peanut (arachis hypogaea) will depend, in part, on its host status for important plant-parasitic nematodes of these crops. the pearl millet hybrid 'tifgrain 102' is resistant to both meloidogyne incognita race 3 and m. arenaria race 1; however, its host statu ... | 2005 | 19262863 |
| influence of poultry litter applications on nematode communities in cotton agroecosystems. | the effects of the application of poultry litter at 0.0, 6.7, 13.4, and 20.1 tons/ha on population changes during the growing season on nematode communities were evaluated in two cotton production fields in north carolina. numbers of bactivorous nematodes increased at midseason in response to the rate at which litter was applied but decreased with increasing litter application rates at cotton harvest. numbers of fungivores at cotton harvest were related positively to the rate of litter applied, ... | 2004 | 19262834 |
| pasteuria thornei sp. nov. and pasteuria penetrans sensu stricto emend., mycelial and endospore-forming bacteria parasitic, respectively, on plant-parasitic nematodes of the genera pratylenchus and meloidogyne. | descriptions are presented of two members of the pasteuria penetrans group of mycelial and endospore-forming bacteria, parasitic on plant-parasitic nematodes. in one case, the epithet p. penetrans sensu stricto emend. has now been limited to members of this group with cup-shaped sporangia and ellipsoidal endospores, parasitic primarily on the root-knot nematode meloidogyne incognita. the second organism, with rhomboidal sporangia and nearly spherical endospores, which is parasitic primarily on t ... | 1988 | 3382544 |
| pasteuria nishizawae sp. nov., a mycelial and endospore-forming bacterium parasitic on cyst nematodes of genera heterodera and globodera. | this study describes pasteuria nishizawae sp. nov., a fourth species of the genus pasteuria. this mycelial and endospore-forming bacterium parasitizes the adult females of cyst-forming nematodes in the genera heterodera and globodera. the distinct ultrastructural features and unique host range found for this bacterium separate it from two closely related species, pasteuria penetrans, which parasitizes several species of root-knot nematodes of the genus meloidogyne, and pasteuria thornei, which a ... | 1991 | 1947427 |
| reproduction of pratylenchus brachyurus on soybean callus tissue: effects of culture age and observations on anhydrobiosis. | | 1986 | 19294230 |
| influence of selected cultural practices on winter survival of pratylenchus brachyurus and subsequent effects on soybean yield. | planting date of soybean, glycine max, influenced winter survival of pratylenchus brachyurus in microplots at two locations in north carolina. delayed planting resulted in a linear decrease (p = 0.05) in the numbers of p. brachyurus at soybean harvest. effects of planting date on nematode numbers persisted over winter, indicating that survival in the absence of a host is density independent. compared with winter fallow, winter wheat, triticum aestivum, reduced winter survival of p. brachyurus. s ... | 1985 | 19294125 |
| influence of planting date on population dynamics and damage potential of pratylenchus brachyurus on soybean. | planting date was used as a variable to determine the effects of time and different environmental conditions on the population dynamics and damage potential of pratylenchus brachyurus on soybean at two locations in north carolina. an initial population slightly less than the damage threshold (275 nematodes/500 cm(3) soil) was used to minimize the influence of host damage on this nematode's population dynamics and to gain greater precision in characterizing factors which influence the damage pote ... | 1985 | 19294121 |
| host specificity of four populations of pratylenchus brachyurus. | four populations of the lesion nematode pratylenchus brachyurus were tested in a greenhouse on seven selected plant species to determine host suitability and usefulness in identifying physiological races of the nematode. the differential plants were 'florida 77' alfalfa, 'harvester' snap bean, 'rough lemon' citrus, 'pioneer 304c' corn, 'florunner' peanut, 'braxton' soybean, and 'rutgers' tomato. fresh shoot or root weights of plants inoculated with all populations were similar to each other and ... | 1988 | 19290320 |
| bahiagrass for the management of meloidogyne arenaria in peanut. | bahiagrass (paspalum notatum) cultivars argentine, pensacola, and tifton-9 were non-hosts for meloidogyne arenaria, m. incognita, and heterodera glycines in a greenhouse experiment using field soil infested with these nematodes. the effect of pensacola bahiagrass in rotation with peanut (arachis hypogaea) on m. arenaria was studied in 1986 and 1987 in a field at the wiregrass substation near headland, alabama. each year soil densities of second-stage juveniles of m. arenaria, determined near pea ... | 1988 | 19290315 |
| role of nematodes and soil-borne fungi in cotton stunt. | the nematodes, pratylenchus brachyurus, trichodorus christiei, and t. porosus and the soil-borne fungi, rhizoctonia solani, pythium debaryanum, p. irregulare, p. ultimum, and fusarium spp. were the pathogens most frequently found in the roots and rhizosphere of field-grown cotton (gossypium hirsutum) showing "stunt" symptoms. field-plot application of the nematicide d-d (l,2-dichloropropane, 1,3-dichloropropene) at 373.4 liter/ha (40 gal/a) significantly increased plant growth and yield. a fungi ... | 1971 | 19322335 |
| tillage and multiple cropping systems and population dynamics of phytoparasitic nematodes. | the effect of two cropping and tillage systems on the population dynamics of four nematode species was evaluated on a loamy sand. hairy vetch succeeded by corn or grain sorghum was seeded in split plots randomized within whole plots of no-tillage versus conventional tillage over four growing seasons (1980-83). the vetch-corn cropping system increased the density of meloidogyne incognita 2.9 x more than the vetch-grain sorghum cropping system. in contrast, the vetch-grain sorghum cropping system ... | 1988 | 19290311 |
| results of annual phytoparasitic nematode surveys of arkansas soybean fields, 1978-1986. | results of surveys from 1978 to 1986 to estimate and identify nematodes in arkansas soybean fields are presented. the seven most common nematode species in the fields were heterodera glycines, quinisulcius acutus, pratylenchus scribneri, p. alleni, helicotylenchus pseudorobustus, tylenchorhynchus ewingi, and xiphinema americanum. other nematodes identified from these fields were pratylenchus brachyurus, p. vulnus, p. zeae, tylenchorhynchus canalis, t. goffarti, t. martini, helicotylenchus dihyst ... | 1987 | 19290275 |
| control of pratylenchus brachyurus with selected nonfumigant nematicides on a tolerant and a sensitive soybean cultivar. | a field study was conducted to evaluate soybean cultivar sensitivity to pratylenchus brachyurus and selected nonfumigant nematicides for control of this nematode. 'essex', a tolerant cultivar, yielded more than 'forrest' , a sensitive cultivar, in an infested field. plots treated with aldicarb, carbofuran, and fenamiphos had fewer nematodes 40 days after planting than nontreated plots. plots planted with forrest and treated with carbofuran had a greater yield than the untreated controls. | 1987 | 19290269 |
| interactions between meloidogyne incognita and pratylenchus brachyurus on soybean. | interactions among meloidogyne incognita, pratylenchus brachyurus, and soybean genotype on plant growth and nematode reproduction were studied in a greenhouse. coker 317 (susceptible to both nematodes) and gordon (resistant to m. incognita, susceptible to p. brachyurus) were inoculated with increasing initial population densities (pi) of both nematodes individually and combined. m. incognita and p. brachyurus individually usually suppressed shoot growth of both cultivars, but only root growth on ... | 1988 | 19290187 |
| interaction of three plant-parasitic nematodes on corn and soybean. | interaction of belonolaimus longicaudatus, meloidogyne incognita, and pratylenchus brachyurus on corn and b. longicaudatus, m. incognita, and heterodera glycines on soybean was investigated in micropiots during two seasons for corn and one season for soybean. changes in population densities and effects on plant growth of each nematode on corn or soybean alone and in mixed culture were compared. no interactions occurred on corn in 1987. in 1988, midseason population densities of b. longicaudatus ... | 1990 | 19287797 |
| nematode control related to fusarium wilt in soybean and root rot and zinc deficiency in corn. | nematode and disease problems of irrigated, double-cropped soybean and corn, and zinc deficiency of corn were investigated. ethylene dibromide, phenamiphos, and aldicarb were equally effective for controlling nematodes and increasing yields of corn planted minimum-till and soybean planted in a moldboard plow prepared seedbed. the residual effects on yields of nematicides applied to the preceeding crop occurred during 3 years for soybean and 1 year for corn. fusarium wilt symptoms of soybean that ... | 1985 | 19294099 |
| comparison of populations of pratylenchus brachyurus based on isozyme phenotypes. | enzymes from females of five pratylenchus brachyurus populations and one p. scribneri population were analyzed by isoelectric focusing electrophoresis. of the 18 enzyme systems investigated, only malate dehydrogenase (mdh), phosphoglucomutase (pgm), and phosphoglucose isomerase (pgi) were detected from all five p. brachyurus populations and p. scribneri. faint bands were detected for isocitrate dehydrogenase and phosphogluconate dehydrogenase from one p. brachyurus population. three distinct phe ... | 1990 | 19287755 |
| host range and ecology of isolates of pasteuria spp. from the southeastern united states. | isolates of pasteuria penetrans were evaluated for ecological characteristics that are important in determining their potential as biological control agents. isolate p-20 survived without loss of its ability to attach to its host nematode in dry, moist, and wet soil and in soil wetted and dried repeatedly for 6 weeks. some spores moved 6.4 cm (the maximum distance tested) downward in soil within 3 days with percolating water. the isolates varied greatly in their attachment to different nematode ... | 1990 | 19287753 |
| vertical distribution of plant-parasitic nematodes in sandy soil under soybean. | vertical distribution of five plant-parasitic nematodes was examined in two north florida soybean fields in 1987 and 1988. soil samples were collected from 0-15 cm, 15-30 cm, and 30-45 cm deep at each site. soil at the three depths consisted of approximately 96% sand. more than 50% of belonolaimus longicaudatus population densities occurred in the upper 15-cm soil layer at planting, but the species became more evenly distributed through the other depths as the season progressed. criconemella sph ... | 1990 | 19287693 |
| 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 |
| effects and dynamics of a nematode community on soybean. | the relationships between densities of all members of a plant-parasitic nematode community and yield of 'davis' soybean and between final and preplant population levels were examined in small plots on sandy soils in north-central florida. plant-parasitic nematodes present in the community included belonolaimus longicaudatus, criconemella sphaerocephala, meloidogyne incognita, paratrichodorus minor, pratylenchus brachyurus, and xiphinema sp. plant growth, including stand count, soybean yield (kg/ ... | 1989 | 19287643 |
| effects and dynamics of a nematode community on maize. | relationships between nematode density and yield and between final and preplant population levels were examined in small maize plots on sandy soils in north-central florida. plant-parasitic nematodes present in the community included belonolaimus longicaudatus, criconemella sphaerocephala, meloidogyne incognita, paratrichodorus minor, pratylenchus brachyurus, and a xiphinema sp. plant growth--including stand count, grain yield, stalk weight, and size of young plants--often was inversely correlat ... | 1989 | 19287639 |
| 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 |
| damage and reproductive potentials of pratylenchus brachyurus and p. penetrans on soybean. | damage and reproductive potentials of pratylenchus brachyurus and p. penetrans on soybean, glycine max, cvs. essex, forrest, and lee 68, were determined in microplot tests. cultivar essex was generally tolerant to p. brachyurus. yield of forrest was suppressed linearly with increasing p(i)'s in the sandy soil (r = -0.92) and loamy sand soil (r = -0.99). low to moderate p(i)'s in the sandy clay loam gave an increase in yields as compared to plants without nematodes. yield was not affected by this ... | 1981 | 19300771 |
| interaction of pratylenchus brachyurus and gigaspora margarita on cotton. | an endomycorrhizal fungus, gigaspora margarita, was more effective in stimulating the growth of cotton (gossypium hirsutum) 'coker 201' at a low fertility level (1.77 gm 10-10-10 n-p-k/pot) than doubling the fertility rate for nonmycorrhizal plants. gigaspora margarita alone stimulated shoot growth (height, weight, and flower production by 96%, 553%, and 760%, respectively) and root growth (385%) over that of nonmycorrhizal controls at low fertility. plant development was also stimulated by g. m ... | 1978 | 19305806 |
| population dynamics of plant nematodes in cultivated soil: effects of combinations of cropping systems and nematicides. | the population density of meloidogyne incognita was significantly reduced in land that was fallowed or cropped to crotalaria, marigold, bermudagrass, or bahiagrass. the rate of population decline caused by different cropping systems was influenced by initial population densities. crotalaria, marigold, and bare fallow were about equally effective in reducing the density of m. incognita below dctectable lcvels, usually requiring 1-3 yr. bahiagrass and bcrmudagrass required 4-5 yr or longer to redu ... | 1974 | 19308109 |
| vertical distribution of three namatode species in relation to certain soil properties. | population densities of belonolaimus longicaudatus, pratylenchus brachyurus, and trichodorus christiei were determined from soil samples taken weekly in tifton, georgia during a 14-month period (except for april and may) at 15-cm increments to a depth of 105 cm. belonolaimus longicaudatus predominately inhabited the top 30 cm of soil that was 87-88% sand, 6-7% silt, and 5-7% clay. no specimens were found below 60 cm where the soil was 76-79% sand, 5-6% silt, and 15-19% clay. highest population d ... | 1976 | 19308230 |
| influence of plant-parasitic nematodes on longleaf pine seedlings. | seedlings of longleaf pine (pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. belonolaimus longicaudatus and helicotylenchus dihystera had no effect on seedling growth. high inoculum densities of hoplolaimus galeatus and tylenchorhynchus claytoni caused a significant reduction of fresh weight of seedling roots. root and top weights of seedlings grown in soil infested w ... | 1973 | 19319287 |
| population dynamics of plant nematodes in cultivated soil: length of rotation in newly cleared and old agricultural land. | during a 6-year study of 1-, 2-, and 3-year crop rotations, population densities of pratylenchus brachyurus, trichodorus christiei, and meloidogyne incognita were significantly affected by the choice of crops but not by length of crop rotation. the density of p. brachyurus and t. christiei increased rapidly on milo (sorghum vulgate). in addition, populations of p. brachyurus increased significantly in cropping systems that involved crotalaria (c. rnucronata), millet (setaria italica), and sudang ... | 1973 | 19319315 |
| methyl bromide fumigation of pratylenchus brachyurus in peanut shells. | five dosages of methyl bromide were used to fumigate peanut (arachis hypogaea l.) shells and whole pods of peanuts in 1-liter flasks for 24 hr at 25 c. methyl bromide dosages as low as 24.5 mg/liter killed all pratylenchus brachyurus (godfrey) filip. &sch. stech. in peanut shells. dosages of 44.6 and 50.9 mg/liter killed all but one or two nematodes in shells of whole pods. a 15% reduction in seed germination occurred at the 50.9-mg/liter dosage. | 1973 | 19319321 |
| population dynamics of plant nematodes in cultivated soil: effect of sod-based rotations in tifton sandy loam. | in an 8-year sod-based rotation study, nematode population densities varied with different row-crop sequences and grass sods. in continuous row-crop rotations (cotton-corn-peanut), cotton and corn favored rapid increase of belonolaimus longicaudatus and trichodorus christiei. numbers of pratylenchus brachyurus were quite variable on all crops. peanuts favored an increase of criconemoides ornatum but suppressed the other three species. 'coastal' bermudagrass supported more than twice the number o ... | 1970 | 19322285 |
| population dynamics of plant nematodes in cultivated soil: effect of summer cover crops in old agricultural land. | in a 6-year cover crop sequence study, nematode population densities varied with different cover crops. millet favored rapid increase of belonolaimus longicaudatus and supported relatively large numbers of pratylenchus brachyurus. beggarweed and 'coastal' bermudagrass favored rapid increase of b. iongicaudatus and to a lesser extent p. brachyurus and trichodorus christiei. hairy indigo and crotalaria supported relatively large numbers of p. brachyurus but suppressed b. longicaudatus. hairy indig ... | 1970 | 19322288 |
| population dynamics of plant nematodes in cultivated soil: effect of summer cover crops in newly cleared land. | five nematode species were studied for ability to develop on seven summer cover crops in rotation with tomato transplants grown every third year. increase of tylenchorhynchus claytoni, trichodorus christiei, pratylenchus brachyurus, helicotylenchus dihystera, and xiphinema americanum in newly cleared soil varied with different cover crops. no substantial nematode population increases occurred until the third summer of crop growth. all species except x. americanum and h. dihystera developed best ... | 1970 | 19322300 |
| interactions between meloidogyne incognita, m. hapla, and pratylenchus brachyurus in tobacco. | in a greenhouse pot experiment on the pathogenicity and interactions of meloidogyne incognita, m. hapla and pratylenchus brachyurus on four cultivars o f tobacco the cultivars 'hicks' and 'nc 2326' were susceptible to each nematode and "nc 95' and 'nc 2512' resistant only to m. incognita.mean heights of susceptible plants were depressed but fresh weight of tops did not differ significantly. meloidogyne spp. increased fresh weight of susceptible (but not the resistant) roots.reproduction of m. in ... | 1970 | 19322321 |
| nematodes parasitic on forest trees: iii. reproduction on selected hardwoods. | the host-parasite relationships of 13 species of plant parasitic nematodes and five species of hardwoods native to the southeastern united states were tested on greenhouse-grown tree seedlings for 6-10 months. criteria for parasitism were completion o f life cycle and population increase of nematodes. belonolaimus longicaudatus, helicotylenchus dihystera, scutellonema brachyurum and tylenchorhynchus claytoni parasitized and reproduced on three or more of the species tested. hoplolaimus galeatus ... | 1971 | 19322363 |
| pathogenicity of the lesion nematode, pratylenchus brachyurus, on six soybean cultivars. | pathogenicity tests of pratylenchus brachyurus on selected greenhouse-grown soybean cultivars indicated the nematode reduced seed yield of 'hood' but not that of 'custer', 'bragg', 'dyer', or 'pickett'. root weights of all cultivars were reduced. damage and numbers of nematodes within soybean roots growing at 13, 21, and 29 c were greater at higher temperatures. at 29 c, root pruning was prominent in 'hood' and 'pickett' but limited in 'custer' and 'hill'. root pruning was not observed at 13 c a ... | 1971 | 19322373 |
| influence of incubation solution on the rate of recovery of pratylenchus brachyurus from cotton roots. | the rate of recovery of pratylenchus brachyurus from cotton roots was enhanced when the tissue was incubated in solutions containing 10 ppm ethoxyethyl mercuric chloride, 50 ppm dihydrostreptomycin sulfate, 50, 100, or 1,000 ppm diisobutylphenoxethyl dimethyl benzyl ammonium chloride, or mixtures of these compounds. incubation in 10 or 100 ppm zinc sulfate, zinc chloride, or magnesium chloride also enhanced the rate of recovery. incubation solutions containing 1 or 1,000 ppm zinc chloride or mag ... | 1971 | 19322395 |
| temperature effects on reproduction and pathogenicity of pratylenchus coffeae and p. brachyurus and survival of p. coffeae in roots of citrus jambhiri. | optimum temperature for reproduction of pratylenchus coffeae on rough lemon, citrus jambhiri lush. was 29.5 c. pratylenchus coffeae populations reached 7653 per g of root 2 months after initial inoculation with 140 nematodes. maximum plant weight reduction was 38%; root weights were reduced by as much as 47%. pratylenchus brachyurus significantly reduced plant and root weights but population sizes never approached those of p. coffeae. pratylenchus coffeae survived in stored excised roots and wer ... | 1971 | 19322397 |
| extraction efficiency of belonolaimus longicaudatus from sandy soil. | numbers of belonolaimus longicaudatus extracted from sandy soils (91-92% sand) by sieving and centrifugation were only 40-55% of those extracted by sieving and incubation on a baermann tray. residues normally discarded at each step of the sieving plus baermann tray extraction procedure were examined for nematodes to obtain estimates of extraction efficiencies. for third-stage and fourth-stage juveniles, males, and females, estimates of extraction efficiency ranged from 60 to 65% in one experimen ... | 1991 | 19283162 |
| comparison of millet and sorghum-sudangrass hybrids grown in untreated soil and soil treated with two nematicides. | aldicarb and bay 68138 (ethyl 4-(methylthio)-m-tolyl isopropylphosphoramidate) were effective in increasing the plant height and yield of millet and sorghum-sudangrass hybrids. stunting of plants and reduction in yield were inversely proportional to the number of pratylenchus spp. and belonolaimus longicaudatus present in the rhizosphere. millet and sorghum-sudangrass hybrids supported large numbers of criconemoides ornatus, pratylenchus spp., b. longicaudatus, and xiphinema americanum. funk's s ... | 1973 | 19319298 |
| population dynamics of plant-parasitic nematodes on cover crops of corn and sorghum. | buildup of plant-parasitic nematode populations on corn (zea mays), soybean (glycine max), and sorghum (sorghum bicolor) were compared in 1991 and 1992. final population densities (pf) of meloidogyne incognita were lower following sorghum than after soybean in both seasons, and pf after sorghum was lower than pf after corn in 1992. in both seasons, pf differed among the sorghum cultivars used. no differences in pf on corn, sorghum, and soybean were observed for criconemella spp. (a mixture of c. ... | 1993 | 19279793 |
| comparison of nematode population densities on six summer crops at seven sites in north florida. | densities of plant-parasitic nematodes were compared on six crops grown for forage during the summer of 1991 at seven sites in north central florida. the cropping treatments were 'howard' soybean (glycine max), 'deltapine 105' soybean, velvetbean (mucuna deeringiana), 'california blackeye #5' cowpea (vigna unguiculata), 'pioneer 3098' tropical corn (zea mays), and 'asgrow chaparral' sorghum (sorghum bicolor). highest final densities (pf) of meloidogyne incognita and criconemella spp. were obtain ... | 1992 | 19283048 |
| nematode densities associated with corn and sorghum cropping systems in florida. | final densities (pf) of meloidogyne incognita and pratylenchus spp. increased more than ten-fold over initial densities (pi) on corn (zea mays) cultivars grown at three sites in north florida. the pf of m. incognita following sorghum (sorghum bicolor) were much lower (p </=0.001) than pf following corn at the two sites in which sorghum was grown. at one of these sites, pf of m. incognita was </= 5/100 cm(3) soil, and at the other site pf < pi. at one site, population densities of criconemella sp ... | 1991 | 19283182 |
| 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 |
| managing nematode population densities on tomato transplants using crop rotation and a nematicide. | millet, milo, soybean, crotalaria, and norman pigeon pea were used in conjunction with clean fallow and a nematicide (fensulfothion) for managing nematode populations in the production of tomato transplants (lycopersicon esculentum mill.). glean fallow was the most effective treatment in suppressing nematode numbers. after 2 years in tomato, root-knot nematodes increased in numbers to damaging levels, and fallow was no longer effective for complete control even in conjunction with fensulfothion. ... | 1980 | 19300664 |
| 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 |
| influence of concomitant pratylenchus brachyurus and meloidogyne spp. on root penetration and population dynamics. | populations of pratylenchus brachyurus on cotton were increased significantly in the presence of either meloidogyne incognita or m. arenaria.this occurred with either simultaneous inoculation or prior invasion by m. incognita. p. brachyurus penetrated cotton roots previously invaded by, or simultaneously inoculated with, m. incognita, as well as, or better than, in the absence of m. incognita. prior invasion by m. incognita, however, suppressed p. brachyurus populations on tomato, while it had n ... | 1973 | 19319334 |