| influence of ring nematode infestation and calcium, nitrogen, and indoleacetic acid applications on peach susceptibility to pseudomonas syringae pv. syringae. | abstract two field experiments were conducted to study the effects of added nitrogen, calcium, and indoleacetic acid, in the presence or absence of ring nematodes (mesocriconema xenoplax), on susceptibility of peach to bacterial canker. when noninfested soil was inoculated with ring nematodes, peach tree susceptibility to bacterial canker infection caused by pseudomonas syringae pv. syringae was dramatically increased after a period of 2 years. however, no evidence was found that ring nematode i ... | 2006 | 18943178 |
| nematode and grape rootstock interactions including an improved understanding of tolerance. | sixteen cultivars of grape were screened over a two-year period in the presence or absence of 10 different nematode populations. populations of meloidogyne spp., xiphinema index, and mesocriconema xenoplax developed more rapidly and caused greater damage than populations of x. americanum and tylenchulus semipenetrans. populations of mixed meloidogyne spp. having a history of feeding on grape were among the fastest developing populations. tolerance to nematode parasitism appeared to be based on d ... | 2006 | 19259534 |
| effect of entomopathogenic nematodes on mesocriconema xenoplax populations in peach and pecan. | the effect of steinernema riobrave and heterorhabditis bacteriophora on population density of mesocriconema xenoplax in peach was studied in the greenhouse. twenty-one days after adding 112 m. xenoplax adults and juveniles/1,500 cm(3) soil to the soil surface of each pot, 50 infective juveniles/cm(2) soil surface of either s. riobrave or h. bacteriophora were applied. another entomopathogenic nematode application of the same density was administered 3 months later. the experiment was repeated on ... | 2004 | 19262805 |
| effects of mesocriconema xenoplax on vitis vinifera and associated mycorrhizal fungi. | previous surveys of vineyards had indicated that mesocriconema xenoplax was present in 85% of vineyards in western oregon, but yields were not depressed in established vines. microplot studies were initiated in 1997 in a willamette valley vineyard to determine the impact of m. xenoplax on vine establishment. plots were infested with 0.03, 0.6, and 3.0 m. xenoplax g(-1) soil and planted with self-rooted chardonnay and pinot noir vines. in november 2000, four growing seasons after planting, prunin ... | 2004 | 19262807 |
| population characteristics and dosage trajectory analysis for mesocriconema xenoplax in california prunus orchards. | the mesocriconema xenoplax population increased exponentially in a newly planted peach orchard. the rate of increase was greater on nemaguard than on lovell rootstock and was reduced by postplant nematicides. population levels were more stable in an established almond orchard on nemaguard rootstock. all life stages of the nematode were present year round; lower ratios of juveniles to adults in summer suggested adverse effects of temperature and dry soil. also in summer, there was a smaller propo ... | 2004 | 19262832 |
| biological control of the phytoparasitic nematode mesocriconema xenoplax on peach trees. | seven fluorescent pseudomonas spp. capable of inhibiting reproduction of mesocriconema xenoplax have been isolated from soil sites that suppress both nematode multiplication and peach tree short life (ptsl). one of these seven strains, pseudomonas sp. bg33r, inhibits m. xenoplax multiplication in vivo and egg hatch in vitro. mesocriconema xenoplax populations on peach seedlings inoculated with bg33r and planted into soil-solarized field plots remained at or below the economic threshold for nemat ... | 2002 | 19265918 |
| host suitability of the olive cultivars arbequina and picual for plant-parasitic nematodes. | host suitability of olive cultivars arbequina and picual to several plant-parasitic nematodes was studied under controlled conditions. arbequina and picual were not suitable hosts for the root-lesion nematodes pratylenchus fallax, p. thornei, and zygotylenchus guevarai. however, the ring nematode mesocriconema xenoplax and the spiral nematodes helicotylenchus digonicus and h. pseudorobustus reproduced on both olive cultivars. the potential of meloidogyne arenaria race 2, m. incognita race 1, and ... | 2003 | 19265971 |
| 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 |
| plant-parasitic nematodes associated with grapevines, vitis vinifera, in oregon vineyards. | a survey of vineyards in western oregon was conducted in 1994 and 1995 to determine the association of plant-parasitic nematodes with vine health. seventy vineyards in four regions of western oregon (16 to 21 vineyards per region) were sampled. the regions were the northern, middle, and southern willamette valley, and southern oregon. vineyards were selected and partitioned into blocks by variety, age of planting, crop history, and soil characteristics. mesocriconema xenoplax, xiphinema american ... | 1999 | 19270927 |
| interrelationships among macrophomina phaseolina, criconemella xenoplax, and tylenchorhynchus annulatus on grain sorghum. | microplot experiments were established in 1992, 1993, and 1994 to investigate the relationships among macrophomina phaseolina, criconemella xenoplax, mad tylenchorhynchus annulatus on grain sorghum in louisiana. a factorial treatment arrangement of two grain sorghum hybrids (de kalb dk 50 and pioneer hybrid 8333), three levels of m. phaseolina (0, 10, and 100 colony-forming units (cfu)/g soil), and three nematode inoculum levels (0, 1x, and 2x) were used. nematode inocula at 1x levels were 929, ... | 1997 | 19274150 |
| competition between tylenchorhynchus annulatus and mesocriconema xenoplax on grain sorghum as influenced by macrophomina phaseolina. | greenhouse experiments were conducted to examine competition between tylenchorhynchus annulatus and mesocriconema xenoplax on grain sorghum roots that were colonized by the fungus macrophomina phaseolina or free from fungus colonization. an incomplete factorial treatment design consisted of two levels of m. phaseolina (0 or 10 colony-forming units/g soil) and 12 t. annulatus:m. xenoplax ratios: 1,000:0; 750:0; 500:0; 250:0; 0:0; 0:250; 0:500; 0:750; 0:1,000; 750:250; 500:500; and 250:750. plants ... | 1998 | 19274235 |
| 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 |
| parasitism of nematodes by the fungus hirsutella rhossiliensis as affected by certain organic amendments. | experiments were conducted to determine whether the addition of organic matter to soil increased numbers of bacterivorous nematodes and parasitic activity of the nematophagous fungus hirsutella rhossiliensis. in a peach orchard on loamy sand, parasitism of the plant-parasitic nematode criconemella xenoplax by h. rhossiliensis was slightly suppressed and numbers of c. xenoplax were not affected by addition of 73 metric tons of composted chicken manure/ha. in the laboratory, numbers of bacterivoro ... | 1994 | 19279878 |
| effect of lime on criconemella xenoplax and bacterial canker in two california orchards. | in a peach orchard with an initial soil ph of 4.9, preplant application of 0, 13.2, 18.2, 27.3, or 54.2 kg lime/tree site altered soil ph (range after 1 year = 4.8-7.3) but did not affect numbers of criconemella xenoplax or tree circumference. liming also failed to reduce the incidence of bacterial canker, which affected 17% of the trees by the sixth year after planting. four years after planting, numbers of c. xenoplax exceeded 400/100 cm(3) soil, regardless of treatment. trees with higher dens ... | 1994 | 19279934 |
| 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 |
| tests for transmission of prunus necrotic ringspot and two nepoviruses by criconemella xenoplax. | in two of three trials, detectable color reactions in elisa for prunus necrotic ringspot virus (pnrsv) were observed for criconemella xenoplax handpicked from the root zone of infected peach trees. criconemella xenoplax (500/pot) handpicked from root zones of peach trees infected with pnrsv failed to transmit the virus to cucumber or peach seedlings. the nematode also failed to transmit tomato ringspot (tomrsv) or tobacco ringspot viruses between cucumbers, although xiphinema americanum transmit ... | 1990 | 19287748 |
| effect of combining soil solarization with certain nematicides on target and nontarget organisms and plant growth. | field experiments compared pesticidal and plant growth effects of soil solarization, alone and in combination, with overall applications of several nematicides. nematodes, including meloidogyne incognita j2, that were targeted for control were significantly reduced (p < 0.05) by solarization, 1,3-dichloropropene (44 and 132 liter/ha), ethoprop (13.5 kg/ha), metham sodium (64 liter/ha), formaldehyde (111 liter/ha), and by solarization-nematicide combinations. control of pythium ultimum also was o ... | 1987 | 19290287 |
| association of criconemella xenoplax and fusarium spp. with root necrosis and growth of peach. | criconemella xenoplax, fusarium solani, and f. oxysporum caused necrosis of nemaguard peach feeder roots in greenhouse tests. root necrosis was more extensive in the presence of either fungus than wtih c. xenoplax alone. shoot growth and plant height were less for plants inoculated with f. oxysporum or f. solani than for plants inoculated with the fungi plus c. xenoplax. neither synergistic nor additive effects on root necrosis or plant growth occurred between c. xenoplax and the fungal pathogen ... | 1986 | 19294169 |
| criconematina (nematoda: tylenchida) from the aleutian islands. | a new genus (cerchnotocriconenta) and three new species (c. psephinum, hemicycliophora amchitkaensis, and paratylenchns amundseni) are described from adak and amchitka islands in the aleutian chain. the new genus differs from all other criconematid genera in having irregular, convex sculpturing consisting of small, oval plates on the anterior and posterior regions of each annule, with the mid-annular region minutely punctate or dentate. h. arnchitkaensis n. sp. resembles h. similis thorne and h. ... | 1982 | 19295715 |
| effect of planting site preparation, hydrated lime, and dbcp (1, 2-dibromo-3-chloropropane) on populations of macroposthonia xenoplax and peach tree short life in georgia. | annual postplanting applications of 40.7 kg/ha dbcp (1,2-dibromo-3-chloropropane) controlled macroposthonia xenoplax (raski, 1952) degrisse and loof, 1965 in peach tree short life sites, reduced bacterial canker incidence from 74% to 6%, and inreased the average life of the trees from 3.9 to 6.8 yr for a 7-yr test period. hydrated lime at 5.5 kg per planting site reduced bacterial canker incidence from 81% 57 % and increased the tree longevity from 2.6 to 6.0 yr. populations m. xenoplax were inv ... | 1982 | 19295753 |
| response of pinus ponderosa seedlings to stylet-bearing nematodes. | of 12 stylet-bearing nematodes used for inoculations, pratylenchus penetrans, p. brachyurus, p. vulnus, ditylenchus destructor, meloidogyne incognita, m. javanica, and m. hapla reproduced on pinus ponderosa, while xiphinema index, aphelenchus avenae, paratylenehus neoamblycephalus, tylenchulus semipenetrans, and macroposthonia xenoplax did not. p. vulnus, p. brachyurus, p. penetrans, a. avenae, d. destructor, t. semipenetrans, and p. neoamblycephalus significantly suppressed both the shoot and r ... | 1979 | 19300659 |
| effects of nematicides, lime, and herbicide on peach tree short life in georgia. | peach tree mortality was 75% five years after planting on a site associated with peach tree short life and receiving no nematicide treatment, no lime, and with cultivation for weed control. mortality was reduced to 29% by preplanting plus postplanting applications of dbcp (1,2-dibromo-3-chloropropane) and with herbicidal weed control. preplanting applications of nematicides alone did not effectively reduce tree mortality or increase yield. lime applications increased yield but did not affect tre ... | 1980 | 19300693 |
| association of macroposthonia xenoplax and scutellonema brachyurum with the peach tree short life syndrome. | high populations of both scutellonema brachyurum and macroposthonia xenoplax were detected in the root zones of peach trees growing at sites where peach tree short life occurred. both nematodes responded to changes in tree health, with the highest numbers detected under the most vigorous trees; both populations declined as tree vigor declined. few of either species were detected 6 months after trees died. the nematode populations were inversely correlated with each other. more m. xenoplax were r ... | 1981 | 19300749 |
| effects of macroposthonia xenoplax on the growth of concord grape. | concord grape (vitis labrusca) plants were inoculated with macroposthonia xenoplax at levels of 100, 1,000, and 10,000 nematodes. after 4 months, plants inoculated with 10,000 m. xenoplax were stunted, and root systems were darker and had fewer feeder roots than those in other treatments. the lower nematode inoculation levels suppressed top growth but did not affect root growth. m. xenoplax reproduced well on concord grapes. | 1977 | 19305597 |
| influence of nemaguard and lovell rootstocks and macroposthonia xenoplax on bacterial canker of peach. | 'fay elberta' peach trees grown on either 'lovell' or 'nemaguard' rootstocks in sandy soil in a lathhouse were highly susceptible to bacterial canker if inoculated with the nematode macroposthonia xenoplax and the bacterium pseudomonas syringae. if either one of these organisms were omitted, serious bacterial canker did not develop. cankers appeared later and remained small when nematodes were omined. very few cankers appeared on trees not inoculated with the bacterium. peach trees on both roots ... | 1977 | 19305599 |
| pathogenicity of macroposthonia xenoplax to walnut. | preplanting treatment of soil naturally infested with macroposthonia xenoplax with 1,2-dibromoethane (ethylene dibromide) significantly increased the growth rate of juglans hindsii seedlings. when seedlings of j. hindsii, j. regia cv "serf" and j. regia cv eureka were inoculated with m. xenoplax, their growth was signilicantly less than that of nematode-free controls. this retarded growth rate was accompanied hy feeder root necrosis, longitudinal cracks in the older roots, and distinct lesions i ... | 1978 | 19305847 |
| pathogenicity of criconemoides xenoplax to prune and plum rootstocks. | elimination of criconemoides xenoplax from a prune orchard soil by fumigation with ethylene dibromide at the rate of 42 muliter/liter of soil (equivalent to about 13 gal/acre) improved the growth of myrobalan plum, addition of this nematode to myrobalan seedlings or young 'marianna 2624' plants propagated from cuttings resulted in destruction of cortical root tissue, darkening of roots, alteration of water stress, lowering of nutrient levels in leaves, and reduction in plant weight. c. xenoplax ... | 1975 | 19308143 |
| susceptibility of japanese holly to criconemoides xenoplax, tylenchorhynchus claytoni, and certain other plant-parasitic nematodes. | three cultivars of ilex crenata: 'helleri', 'convexa', and 'rotundifolia' were inoculated with either criconemoides xenoplax, helicotylenchus dihystera, hoplolaimus galeatus, trichodorus cltristiei, or tylenchorhynchus claytoni at 0, 200 (low), or 2,000 (high) nematodes/ 15-cm diam pot. plants were kept in the greenhouse 10 mo prior to transplanting into 2.25 m(2) field plots. helleri was severely stunted by c. xenoplax. criconemoides xenoplax and t. claytoni caused lower plant vigor and top wei ... | 1976 | 19308191 |
| 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 |
| interaction of concurrent populations of meloidogyne partityla and mesocriconema xenoplax on pecan. | the effect of the interaction between meloidogyne partityla and mesocriconema xenoplax on nematode reproduction and vegetative growth of carya illinoinensis 'desirable' pecan was studied in field microplots. meloidogyne partityla suppressed reproduction of m. xenoplax, whereas the presence of m. xenoplax did not affect the population density of m. partityla second-stage juveniles in soil. above-ground tree growth, as measured by trunk diameter 32 months following inoculation, was reduced in the ... | 2008 | 19440263 |
| resistance of grape rootstocks to plant-parasitic nematodes. | candidate grape rootstocks were selected through a rigorous screening program initiated with important sources of resistance to meloidogyne pathotypes and to xiphinema index in muscadinia rotundifolia and vitis species native to north america. based on their rooting capability and horticultural characteristics, 200 candidates were selected from 5,000 progeny of multiple crosses between commercial grape rootstocks and wild grape species that exhibited resistance to nematodes. after a 15-year scre ... | 2012 | 23482972 |
| diversity and occurrence of plant-parasitic nematodes associated with golf course turfgrasses in north and south carolina, usa. | one hundred and eleven golf courses from 39 counties in the carolinas were surveyed for plant-parasitic nematodes. species diversity within habitats was analyzed with five diversity indices including diversity index (h'), evenness (j'), richness (sr), dominance (λ) and diversity (h2 ). the results revealed a remarkably high diversity of 24 nematode species belonging to 19 genera and 11 families. of those, 23 species were found in sc, 19 species in nc, and 18 species were detected in both states. ... | 2012 | 23482422 |
| bacterial selection for biological control of plant disease: criterion determination and validation. | this study aimed to evaluate the biocontrol potential of bacteria isolated from different plant species and soils. the production of compounds related to phytopathogen biocontrol and/or promotion of plant growth in bacterial isolates was evaluated by measuring the production of antimicrobial compounds (ammonia and antibiosis) and hydrolytic enzymes (amylases, lipases, proteases, and chitinases) and phosphate solubilization. of the 1219 bacterial isolates, 92% produced one or more of the eight co ... | 2016 | 27765523 |
| parasitic and saprophytic abilities of the nematode-attacking fungus hirsutella rhossiliensis. | the ability of hirsutella rhossiliensis to colonize various substrates in sterile and nonsterile soil was measured. hirsutella rhossiliensis was recovered from 67% and 77% of living, inoculated criconemella xenoplax incubated in sterile and nonsterile soil, respectively. in contrast, the fungus was recovered from 100% and 18% of heat-killed, inoculated nematodes incubated on sterile and nonsterile soil, respectively. hirsutella rhossiliensis was readily recovered from inoculated, autoclaved whea ... | 1985 | 19294104 |
| spot drip application of dimethyl disulfide as a post-plant treatment for the control of plant parasitic nematodes and soilborne pathogens in grape production. | plant parasitic nematodes and soilborne pathogens can reduce the overall productivity in grape production. not all grape growers apply soil fumigants before planting, and there is no single rootstock resistant to all nematode species. the aim of this investigation was to evaluate the effect of dimethyl disulfide (dmds) applied at 112, 224, 448 and 897 kg ha(-1) as a post-plant treatment against soilborne plant parasitic nematodes and pathogens on the grape yield in established grapevines. | 2014 | 24307137 |
| population genetics of hirsutella rhossiliensis, a dominant parasite of cyst nematode juveniles on a continental scale. | hirsutella rhossiliensis is a parasite of juvenile nematodes, effective against a diversity of plant-parasitic nematodes. its global distribution on various nematode hosts and its genetic variation for several geographic regions have been reported, while the global population genetic structure and factors underlying patterns of genetic variation of h. rhossiliensis are unclear. in this study, 87 h. rhossiliensis strains from five nematode species (globodera sp., criconemella xenoplax, rotylenchu ... | 2016 | 27542936 |
| in vitro parasitism of rotylenchus robustus by isolates of hirsutella rhossiliensis. | we tested the hypothesis that isolates of hirsutella rhossiliensis from host nematodes in the family hoplolaimidae (rotylenchus robustus and hoplolaimus galeatus) would be more virulent to r. robustus than would isolates from host nematodes not in the hoplolaimidae (heterodera schachtii and criconemella xenoplax). nematodes were touched to 10-20 spores of different isolates and incubated at 20 c in 4.5 mm kc1; the percentage of nematodes colonized (filled with hyphae) was determined after 2, 5, ... | 1995 | 19277317 |
| suppression of cyst nematode by natural infestation of a nematophagous fungus. | penetration of cabbage roots by heterodera schachtii was suppressed 50-77% in loamy sand naturally infested with the nematophagous fungus hirsutella rhossiliensis. when heterodera schachtii was incubated in the suppressive soil without plants for 2 days, 40-63% of the juveniles had hirsutella rhossiliensis spores adhering to their cuticles. of those with spores, 82-92% were infected. infected nematodes were killed and filled with hyphae within 2-3 days. addition of kcl to soil did not increase i ... | 1989 | 19287645 |
| spatial distribution of plant-parasitic nematodes in semi-arid vitis vinifera vineyards in washington. | the most commonly encountered plant-parasitic nematodes in eastern washington vitis vinifera vineyards are meloidogyne hapla, mesocriconema xenoplax, pratylenchus spp., xiphinema americanum, and paratylenchus sp.; however, little is known about their distribution in the soil profile. the vertical and horizontal spatial distribution of plant-parasitic nematodes was determined in two washington v. vinifera vineyards. others variables measured in these vineyards included soil moisture content, fine ... | 2014 | 25580024 |
| population trends and vertical distribution of plant-parasitic nematodes associated with vitis labrusca l. in michigan. | nematode population trends and vertical distribution were monitored in a southwest michigan vineyard (vitis labrusca cv. concord) from 1976 through 1983. shallow (20 cm) and deep (90 cm) applications of 1,3-dichloropropene applied at 281 (shallow) plus 658 or 1,122 (deep) liters/ ha provided excellent control of xiphinema americanum, criconemella xenoplax, and meloidogyne hapla. populations of x. americanum remained below detectable levels for the entire 8-year experimental period where the fumi ... | 1985 | 19294066 |
| impact of meloidogyne incognita on the incidence of peach tree short life in the presence of criconemella xenoplax. | the relationship between cricenemella xenoplax alone and in combination with meloidogyne incognitaon the incidence of peach tree short life disease was studied in field microplots during 1989-96. the presence of m. incognita suppressed the population density of c. xenoplax on lovell peach. tree trunk diameter was significantly reduced in the presence of both nematode species prior to 1993. soil ph was lowest in the co-infection treatment as compared with the uninoculated control on three of the ... | 1997 | 19274276 |
| dynamics of concomitant populations of meloidogyne incognita and criconemella xenoplax on peach. | the interaction between meloidogyne incognita and criconemella xenoplax on nematode reproduction and growth of lovell peach was studied in field microlots and the greenhouse. meloidogyne incognita suppressed reproduction of c. xenoplax in both field and greenhouse experiments. tree growth, as measured by trunk diameter, was reduced (p </= 0.05) in the presence of m. incognita as compared with c. xenoplax of the uninoculated control trees 26 months following inoculation. a similar response regard ... | 1993 | 19279823 |
| nematodes attacking cultivars of peach in north carolina. | criconemoides xenoplax and meloidogyne incognita were the nematode species most frequently associated with peach in north carolina. other nematodes often found in high numbers on that crop were pratylenehus vulnus, helicotylenchus spp., trichodorus christiei, xiphinema amerieanum and tylenchorhynchus claytoni. p. vulnus and p. penetrans reproduced well on rootstocks of 21 peach cultivars tested in the greenhouse. p. zeae, p. brachyurus, p. coffeae and p. scribneri decreased or increased only sli ... | 1973 | 19319348 |
| soil temperature effects on the interaction of grape rootstocks and plant-parasitic nematodes. | resistance to meloidogyne spp. in commonly used resistant grape rootstocks is slightly compromised at soil temperatures above 27°c. newly released ucd-grn series rootstocks, which have broad nematode resistance, exhibit trace infections by meloidogyne spp. at elevated temperature. pathotypes of m. incognita and m. arenaria that are virulent on 'harmony' rootstock, as well as m. incognita race 3, which is avirulent on 'harmony', failed to produce egg masses on the ucd-grn series rootstocks and ot ... | 2013 | 23589660 |
| morphological and molecular characterization of discocriconemella inarata, an endemic nematode from north american native tallgrass prairies. | discocriconemella inarata, a plant parasitic nematode species originally discovered in a virgin tallgrass prairie in northwest iowa, was re-examined by molecular and morphological analyses of topotype material. this species has never been recorded in cultivated fields and could potentially serve as an indicator for high quality prairie habitats. dna sequence from a conserved 3' portion of the 18s ribosomal gene exhibited an identical match between d. inarata topotype specimens and topotype speci ... | 2010 | 22736835 |
| populations of criconemella xenoplax on peach interplanted with certain herbaceous plants. | peach trees growing in field microplots infested with criconemella xenoplax were interplanted with centipedegrass, goosegrass, sicklepod, marigold, buckhorn plantain, showy crotalaria, or perennial ryegrass, or left with weed-free soil as the control. buckhorn plantain reduced nematode numbers, but not to levels acceptable for commercial control. marigold, sicklepod, and goosegrass reduced nematode numbers on some sampling dates but not on others. other plants had no effect or appeared to stimul ... | 1992 | 19283046 |
| evaluation of host suitability in prunus for criconemella xenoplax. | methods were developed for screening prunus selections for host suitability to criconemella xenoplax. the relative host suitability of selections was based upon a doubling accumulation value (beta) that was defined as the number of degree-days (base 9 c) required for doubling of an increment of the initial nematode population. the beta value characteristic for c. xenoplax (139 +/- 8 degree-days) on suitable hosts was similar to the average beta value determined for several peach rootstocks known ... | 1991 | 19283144 |
| degree-day models for predicting egg hatch and population increase of criconemella xenoplax. | a degree-day model was derived to predict egg hatch for criconemella xenoplax. eggs collected from gravid females were incubated in distilled water at constant temperatures of 10-35 c. sixty-six percent of all eggs hatched between 13 and 32 c, and 42% hatched at 10 c. all eggs aborted above 32.5 c. between 25 and 32 c, 8.5 +/- 0.5 days were required for egg hatch. degree-day requirement for egg hatch at 10-30 c was estimated to be 154 +/- 5 with a base of 9.03 +/- 0.04 c. this base of 9 c was ad ... | 1991 | 19283143 |
| influence of potassium on spore germination in the nematophagous fungus, hirsutella rhossiliensis. | | 1990 | 19287767 |
| effects of carbendazim on the nematophagous fungus hirsutella rhossiliensis and the ring nematode. | | 1990 | 19287739 |
| influence of criconemella xenoplax and pruning time on short life of peach trees. | influences of criconemella xenoplax and pruning dates were studied in field microplots with 'nemaguard' peach cuttings on a site not previously planted to peaches. trees with or without c. xenoplax were pruned beginning in december 1984 or march 1985. peach tree short life (ptsl) did not occur in the absence of c. xenoplax. ptsl occurred earlier in december-pruned than in march-pruned inoculated trees. results confirm that "old" peach sites are not required for ptsl to occur. pruning nemaguard a ... | 1990 | 19287694 |
| additional hosts for the ring nematode, criconemella xenoplax. | some common legumes and weeds indigenous to peach orchards in south carolina were tested in greenhouse experiments to determine their host suitability for criconemella xenoplax. legumes that were hosts for the nematode were dwarf english trefoil (lotus corniculatus var. arvensis), big trefoil (l. uliginosis), birdsfoot trefoil (l. corniculatus), narrowleaf birdsfoot trefoil (l. tenuis), ball clover (trifolium nigrescens), rose clover (t. hirtum), subterranean clover (t. subterraneum), striate le ... | 1990 | 19287692 |
| an assay for hirsutella rhossiliensis spores and the importance of phialides for nematode inoculation. | a spore assay was developed to measure the relative density of spores of the nematophagous fungus hirsutella rhossiliensis in soil. orchard soil containing h. rhossiliensis-parasitized criconemella xenoplax was placed in vials and incubated for 0-120 days before the addition of probe nematodes, heterorhabditis heliothidis juveniles. after 18 hours, h. heliothidis were extracted from the soil and examined for adhering spores of h. rhossiliensis. no spores were detected when h. heliothidis were ad ... | 1989 | 19287601 |
| peach leaf senescence delayed by criconemella xenoplax. | fall annual leaf senescence of peach was delayed in the field and in microplots in the presence of criconemella xenoplax. soil from the rhizosphere of orchard trees with greener leaves had ca. 2.5 x more nematodes than soil around trees in a more advanced state of fall senescence. in microplots, monoclonal antibody enzyme immunoassay (eia) of leaf cytokinins indicated that concentration of zeatin riboside-like substances and chlorophyll content were greater in leaves of trees growing in nematode ... | 1988 | 19290258 |
| behavior, parasitism, morphology, and biochemistry of criconemella xenoplax and c. ornata on peach. | host-parasite relationships of criconemella xenoplax and c. ornata on nemaguard peach and common bermudagrass were determined in the greenhouse. criconemella xenoplax reproduced on peach and reduced root volume, height, and dry stem weight after 6 months, compared with the noninfested check. numbers of c. ornata did not increase on peach or influence peach growth, but they did reduce dry top weight and root volume of common bermudagrass, compared with c. xenoplax. criconemella xenoplax and c. or ... | 1988 | 19290183 |
| criconemella spp. in pennsylvania peach orchards with morphological observations of c. curvata and c. ornata. | criconemella xenoplax and c. curvata, previously associated with decline of peach trees in other parts of the united states, were found in 20 of 25 pennsylvania peach orchards. population densities were high in some samples. morphometrics of juveniles and adult females of criconemella curvata and c. ornata, are provided. cuticular crenations were observed on j2 and j3 stages of c. curvata and j2-j4 stages of c. ornata. | 1987 | 19290165 |
| effect of initial population density of criconemella xenoplax on reducing sugars, free amino acids, and survival of peach seedlings over time. | percentage of mortality, growth suppression, and changes in free amino acid and reducing sugar content in root and (or) stem tissue of nemaguard peach seedlings were studied in the greenhouse in relation to time and eight different initial population densities (pi) of criconemella xenoplax. after 90 and 180 days, free amino acid content in root tissue significantly increased with increasing nematode numbers. suppression of root volume, dry root and stem weight, height increase, plant survival, a ... | 1987 | 19290147 |
| the effects of ammonia-generating fertilizer on criconemoides xenoplax in pot cultures. | fertilizer which generated nh was detrimental to criconemoides xenoplax grown in the greenhouse. the fertilizer was lethal to the nematodes in vitro only when it was accompanied by urease-positive bacteria or partially purified urease. the detrimental action of the fertilizer-urease mixture was ntore rapitt at ph 8 than at ph 7. | 1976 | 19308237 |