Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| root cortical cell spherical bodies associated with an induced resistance reaction in monoxenic cultures of meloidogyne incognita. | the root-knot nematode meloidogyne incognita was monoxenically cultured on excised roots of soybean cv. pickett and tomato cv. rutgers in agar media containing either 0 to 1,600 mug/ml ammonium nitrate or 0 to 100 mug/ml urea. observations with scanning and transmission electron microscopy indicated that an elevated concentration of ammonium nitrate or urea inhibited giant cell formation and suppressed nematode development in the infected soybean roots. in the tomato roots, concentrations of amm ... | 1995 | 19277295 |
| characterization of a pathogen-induced potato catalase and its systemic expression upon nematode and bacterial infection. | we have isolated a cdna encoding a catalase (cat2st) by differential screening of a cdna library constructed from potato roots infected with the cyst nematode globodera pallida. expression analysis confirmed the local induction of cat2st and showed that it was highest at the adult stage of the parasite. it also revealed that cat2st was induced in uninfected roots, stems, and leaves of infected plants. localized and systemic induction of cat2st was also observed upon root-knot nematode (meloidogy ... | 1995 | 7655060 |
| optimal release rates for attracting meloidogyne incognita, rotylenchulus reniformis, and other nematodes to carbon dioxide in sand. | movement of vermiform stages of meloidogyne incognita, rotylenchulus reniformis, ditylenchus phyllobius, steinernema glaseri, and caenorhabditis elegans in response to carbon dioxide was studied in 40- and 72-mm-long cylinders of moist sand inside 38-mm-d acrylic tubes. meloidogyne incognita, r. reniformis, and s. glaseri were attracted to co when placed on a linear gradient of 0.2%/cm at a mean co concentration of 1.2%. when co was delivered into the sand through a syringe needle at flow rates ... | 1995 | 19277260 |
| enzymes of the phenylpropanoid pathway in soybean infected with meloidogyne incognita or heterodera glycines. | transcription of genes encoding several enzymes and the activity of some of these enzymes of the phenylpropanoid pathway leading to synthesis of chemical and physical barriers for defense of plants against root pathogens was estimated in susceptible and resistant soybean infected with heterodera glycines race 3 or with meloidogyne incognita race 3. transcription of genes encoding phenylalanine ammonia lyase (pal) and the activity of this enzyme increased in resistant, but not susceptible, soybea ... | 1995 | 19277292 |
| rotations with coastal bermudagrass and fallow for management of meloidogyne incognita and soilborne fungi on vegetable crops. | the efficacy of fallow and coastal bermudagrass (cynodon dactylon) as a rotation crop for control of root-knot nematode (meloidogyne incognita race 1) and soilborne fungi in okra (hibiscus esculentus cv. emerald), squash (cucurbita pepo cv. dixie hybrid), and sweet corn (zea mays cv. merit) was evaluated in a 3-year field trial. numbers of m. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fallow ... | 1995 | 19277312 |
| responses of some common cruciferae to root-knot nematodes. | ten cultivated plants of the family cruciferae were evaluated for susceptibility to meloidogyne arenaria race 1, m. incognita races 1 and 3, and m. javanica in a series of four separate greenhouse tests. after 62-64 days, or 1,032-1,072 degree days (10 c base), several of the crops evaluated showed moderate to severe levels of galling (> 3.0 on 0-5 scale) and moderate numbers of egg masses (>2.0 on 0-5 scale) in response to each of the nematode species and races. among the plants tested, collard ... | 1995 | 19277321 |
| reproduction of meloidogyne arenaria, m. incognita, and m. javanica on sesame. | reproduction of meloidogyne arenaria race 1, m. ineognita races 1 and 3, and m. javanica on 10 cultivars of sesame (sesame indicum) was examined in greenhouse tests. sesame cultivars were also evaluated in a field infested with m. arenaria. sesame was a poor host for m. incognita races 1 and 3 as no sesame genotype supported more than 70 eggs/g root. reproduction of m. arenaria race 1 on sesame varied from 20 eggs/g roots for cultivar sesaco 7cb to 1,570 eggs/g roots for sesaco 119 in the greenh ... | 1995 | 19277331 |
| effect of tropical rotation crops on meloidogyne incognita and other plant-parasitic nematodes. | in a field experiment conducted on sandy soil in florida during the 1993 season, rotation crops of castor (ricinus communis), velvetbean (mucuna deeringina), 'mississippi silver' cowpea (vigna unguiculata), american jointvetch (aeschynomene americana), 'dehapine 51' cotton (gossypium hirsutum), and 'sx-17' sorghum-sudangrass (sorghum bicolor x s. sudanense) were effective in maintaining low population densities (<12/100 cm(3) soil) of meloidogyne incognita race 1, whereas high population densiti ... | 1995 | 19277319 |
| induced resistance to meloidogyne hapla by other meloidogyne species on tomato and pyrethrum plants. | advance inoculation of the tomato cv. celebrity or the pyrethrum clone 223 with host-incompatible meloidogyne incognita or m. javanica elicited induced resistance to host-compatible m. hapla in pot and field experiments. induced resistance increased with the length of the time between inoculations and with the population density of the induction inoculum. optimum interval before challenge inoculation, or population density of inoculum for inducing resistance, was 10 days, or 5,000 infective nema ... | 1995 | 19277310 |
| reproduction of meloidogyne incognito and m. arenaria on tropical corn hybrids. | reproduction ofmeloidogyne incognita and m. arenaria was determined on 25 commercial tropical corn hybrids in greenhouse studies. soil around corn seedlings was infested with 3,000 eggs/plant. reproduction was quantified from counts of egg masses on roots stained with phloxine b 60 days after soil infestation. all of the tropical hybrids were susceptible to m. incognita and m. arenaria. egg mass indices (0-5 scale) ranged from 3.4 to 4.2 and from 3.4 to 4.1 for m. incognita and m. arenaria, resp ... | 1994 | 19279959 |
| tropical rotation crops influence nematode densities and vegetable yields. | the effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north florida from 1991 to 1993. the crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (secale cereale) during winter 1991-92; (iii) 'lemondrop l' squash (cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'classic' eggplant (solanum melo ... | 1994 | 19279897 |
| movement of five nematode species through sand subjected to natural temperature gradient fluctuations. | temperature gradient fluctuations that occur naturally as a result of heating and cooling of the soil surface were reproduced within 15-cm-d, 15-cm-long acrylic tubes filled with moist sand. sunny and rainy periods during the late summer in eastern texas were simulated. five ecologically different nematode species were adapted to fluctuating temperatures for 20-36 hours at a simulated depth of 12.5 cm before being injected simultaneously into the centers of tubes at that depth. when heat waves w ... | 1994 | 19279868 |
| monoclonal antibodies to the esophageal glands and stylet secretions of heterodera glycines. | three monodonal antibodies (mabs) that bound to secretory granules within the subventral esophageal glands of second-stage juveniles (j2) of the soybean cyst nematode (scn), heterodera glycines, were developed from intrasplenic immunizations of a mouse with homogenates of scn j2. two mabs to the secretory granules within subventral glands and one mab to granules within the dorsal esophageal gland of scn j2 were developed by intrasplenic immunizations with j2 stylet secretions. stylet secretions, ... | 1994 | 19279890 |
| interaction between meloidogyne incognita and fusarium oxysporum f. sp. phaseoli on selected bean genotypes. | four bean genotypes (ipa-1, a-107, a-211, and calima), representing all possible combinations of resistance and susceptibility to fusarium oxysporum f. sp. phaseoli (fop) and meloidogyne incognita, were each inoculated with three population densities of these pathogens. calima and a-107 were resistant to fop; a-107 and a-211 were resistant to m. incognita; and ipa-1 was susceptible to both pathogens. in fop-susceptible lines (ipa-1 and a-211), the presence of m. incognita contributed to an earli ... | 1994 | 19279917 |
| response of meloidogyne spp. to pasteuria penetrans, fungi, and cultural practices in tobacco. | the response of a mixed population of meloidogyne incognita and m. javanica to three cultural practices, tobacco cultivars (two cultivars, differing in resistance to m. incognita), cover treatments (three treatments), and inorganic nitrogen fertilizer (two treatments), pasteuria penetrans, and soil-borne fungi was investigated in a tobacco field in 1991. on all sampling dates, higher densities of root-knot nematodes were observed on tobacco cv. coker 371 gold than on k-326. initially, forage sor ... | 1994 | 19279937 |
| host response of ornamental palms to rotylenchulus reniformis. | the responses of 20 species of ornamental palms and one cycad (cycas revoluta) to two populations of the reniform nematode, rotylenchulus reniformis, from southern florida were studied in two greenhouse experiments conducted in 1989-1991 and 1991-92. ornamental palms in pots were exposed to initial population densities of 400 and 1,500 r. reniformis/l00 cm(3) soil for 16 and 15 months, respectively. nematode reproduction occurred on acoelorrhaphe wrightii and washingtonia robusta, but not on the ... | 1994 | 19279956 |
| raphanus sativus, sinapis alba, and fagopyrum esculentum as hosts to meloidogyne incognita, meloidogyne javanica, and plasmodiophora brassicae. | cultivars of oilseed radish (raphanus sativus var. oleifera cv. adagio, nemex, pegletta, renova, siletina, siletta nova, and ultimo), white mustard (sinapis alba cv. albatross, emergo, maxi, martigena, metex, and serval), buckwheat (fagopyrum esculentum cv. prego, tardo), and phacelia (phacelia tanacetifolia cv. angelia) were tested for susceptibility to meloidogyne incognita race 3 and meloidogyne javanica. experiments were conducted in growth chambers at 25 c and 16 hours light for 42 days aft ... | 1994 | 19279960 |
| response of some common annual bedding plants to three species of meloidogyne. | twelve ornamental bedding plant cultivars were grown in soil infested with isolates of meloidogyne incognita race 1, m. javanica, or m. arenaria race 1 in a series of tests in containers in a growth room. root galling (0-5 scale) and eggs/plant were evaluated 8-10 weeks after soil infestation and seedling transplantation. snapdragon, antirrhinum majus cv. first ladies, was extensively galled and highly susceptible (mean gall rating >/=4.2 and >/=14,500 eggs/plant), and celosia argentea cv. centu ... | 1994 | 19279963 |
| identification and analysis of a cuticular collagen-encoding gene from the plant-parasitic nematode meloidogyne incognita. | the vast majority of proteins in the nematode cuticle are collagens. cuticular collagen-encoding genes (col) have been described for the animal parasites ascaris suum and haemonchus contortus and for the free-living caenorhabditis elegans. the proteins encoded by all these genes seem to have the same basic structure, indicating that there is a conserved subfamily of cuticular col in these nematodes. in this paper, we describe the identification and characterization of a cdna (lemmi 5) which corr ... | 1994 | 7828882 |
| the nematophagous fungus verticillium chlamydosporium produces a chymoelastase-like protease which hydrolyses host nematode proteins in situ. | the nematophagous fungus verticillium chlamydosporium secreted several proteases in submerged culture in which soya peptone was the sole carbon and nitrogen source. one protease, vcp1 (m(r) 33,000, pi 10.2), was purified 14-fold from culture filtrates to apparent homogeneity using preparative isoelectric focusing in free solution, and shown to rapidly hydrolyse the chymotrypsin substrate suc-(ala)2-pro-phe-pna and elastin. vcp1 had a km for suc-(ala)2-pro-phe-pna of 4.3 x 10(-5) m and a kcat of ... | 1994 | 8000541 |
| sensitivity of bedding plants to southern root-knot nematode, meloidogyne incognita race 3. | thirty-two cultivars of 10 commonly-grown bedding plants, representing eight families, were evaluated for their response to infection by the root-knot nematode, meloidogyne incognita race 3, under greenhouse conditions. four ageratum cultivars, two marigold, and two salvia cultivars were rated resistant after exposure for 8 weeks. four begonia, four celosia, one dianthus, one verbena, one vinca, and three pansy cultivars were susceptible. three salvia, one begonia, one gerber, one verbena, and t ... | 1994 | 19279964 |
| survey of meloidogyne spp. in tomato production fields of baix llobregat county, spain. | a survey was conducted to determine the frequency and abundance of meloidogyne spp. in tomato production sites located in baix llobregat county, barcelona, spain. forty-five sites were sampled before planting and at harvest from february to october, 1991. meloidogyne spp. occurred in 49% of the sites sampled. preplant population densities ranged from 10 to 220 (x = 110)juveniles/ 250 cm(3) soil, and final population densities ranged from 20 to 1,530 (x = 410)juveniles/250 cm(3) soil. final popul ... | 1994 | 19279955 |
| efficacy of fenamiphos formulations applied through irrigation for control of meloidogyne incognita on squash. | management ofmeloidogyne incognita by chemigation with fenamiphos was studied in an infested field planted to m. incognita-suscepfible yellow summer squash cv. dixie hybrid. fenamiphos (vl 73.1% a.i. manufacturing concentrate in propylene glycol) was mixed with unitol dsr-90 or used as fenamiphos 3 sc (spray concentrate). both formulations, applied with 63.5 kl irrigation water per hectare, decreased numbers of m. incognita second-stage juveniles in the soil and root-gall indices, and increased ... | 1994 | 19279950 |
| efficacy and compatibility for fenamiphos and eptc applied in irrigation water for nematode and weed control in snapbean production. | a nematicide (fenamiphos) and a herbicide (eptc) were injected into a sprinkler irrigation system separately and as tank mixtures and applied in 25.4 kl water/ha for nematode and weed control on snapbean. there were no differences (p = 0.05) between methods of injection of fenamiphos + eptc on efficacy or crop response. the root-gall indices of cultivars eagle and gv 50 were lower in fenamiphos-treated plots than those treated with eptc alone and untreated plots. the yield and crop value were gr ... | 1994 | 19279949 |
| influence of 1,3-dichloropropene, fenamiphos, and carbofuran on meloidogyne incognita populations and yield of chile peppers. | field trials were conducted during 1986, 1988, 1989, and 1991 to compare the effects of 1,3-dichloropropene, fenamiphos, and carbofuran on yield and quality of chile peppers (capsicum annuum) in soil infested with meloidogyne incognita. when compared with untreated plots, numbers of m. incognita juveniles recovered from soil 60 and(or) 90 days after chile pepper emergence were reduced (p = 0.05) following 1,3-d treatment every year except 1986. nematode numbers were also reduced (p = 0.05) by fe ... | 1994 | 19279948 |
| effect of tillage and crop residue management on nematode densities on corn. | effects of winter cover crop management on nematode densities associated with a subsequent corn (zea mays) crop were examined in five sites in north florida. two sites had received winter cover crops of lupine (lupinus angustifolius), and one site each had rye (secale cereale), hairy vetch (vicia villosa), and crimson clover (trifolium incarnatum). in each site, five different management regimes were compared: 1) conventional tillage after the cover crop was removed for forage; 2) conventional t ... | 1994 | 19279946 |
| reaction of ten cultivars of watermelon (citrullus lanatus) to a puerto rican population of meloidogyne incognita. | ten cultivars of watermelon were evaluated for their response to a puerto rican population of meloidogyne incognita under greenhouse conditions in a 2-year study (1989 and 1990). ten-day-old seedlings were planted in steam-sterilized soil in 15-cm-d plastic pots. the nematode inoculum consisted of 10,000 eggs and (or) second-stage juveniles (j2)/plant. the cultivars were sugar baby, charleston gray, seedless, prince charles, charleston 76, jubilee, florida giant, royal charleston, royal sweet, a ... | 1994 | 19279940 |
| optimal levels of meloidogyne incognita inoculum for infection of tomato and peach in vitro. | penetration of second-stage juveniles (j2) of meloidogyne incognita into tomato root explants and in vitro propagated peach plantlet roots were compared. five inoculum levels were used: 25, 50, 75, 100, and 200 j2 for tomato; and 50, 100, 200, 500, and 1,000j2 for peach. the greatest root penetration into tomato was 30% at the 75 j2 level, but the maximum penetration into peach roots was only 8% at the 200 j2 level. the difference (p = 0.05) in penetration of m. incognita at all inoculum levels ... | 1994 | 19279926 |
| partial characterization of cytosolic superoxide dismutase activity in the interaction of meloidogyne incognita with two cultivars of glycine max. | the closely related soybean (glycine max) cultivars centennial and pickett 71 were confirmed to be resistant and susceptible, respectively, to the root-knot nematode meloidogryne incognita. increases in superoxide dismutase (sod) activity were detected in roots of both soybean cultivars 48 hours following inoculation. superoxide dismutase activity increased in roots of the susceptible cultivar overall, but declined after 96 hours in roots of the resistant cultivar. the isoelectric points of sod ... | 1994 | 19279911 |
| low-temperature scanning electron microscope observations of the meloidogyne incognita egg mass: the gelatinous matrix and embryo development. | the root-knot nematode meloidogyne incognita was cultured monoxenically on excised tomato roots. galls and egg masses were observed daily using a light microscope. two phases were distinguished in the gelatinous matrix of the egg mass: a translucent, amorphous material on the surface of the egg mass and a denser, layered phase in which nematode eggs were deposited. egg masses were also cryofixed, fractured, and observed as frozen, hydrated specimens on a cold stage in a scanning electron microsc ... | 1994 | 19279909 |
| trans-splicing of a meloidogyne incognita mrna encoding a putative esophageal gland protein. | a monoclonal antibody, 7a9, specific for antigens in the subventral esophageal glands of adult female meloidogyne incognita and for antigens in the longitudinal muscles of second-stage juveniles, was used to isolate a clone from a m. incognita cdna expression library. the corresponding genomic dna was isolated by hybridization and the gene designated sec-1. dna sequence analysis of sec-1 revealed the presence of 9 introns having structural similarities to introns from the free-living nematode ca ... | 1994 | 7891751 |
| reproduction of virulent isolates of meloidogyne incognita on susceptible and mi-resistant tomato. | the reproductive potential of natural and laboratory-selected meloidogyne incognita isolates virulent against the tomato mi resistance gene, all derived from a single egg-mass, were compared when the nematodes were inoculated on susceptible and resistant tomato. fewer second-stage juveniles (p = 0.01) of the two virulent populations selected under laboratory conditions matured to females on the resistant tomato compared to the susceptible cultivar. in contrast, no differences were found between ... | 1994 | 19279899 |
| penetration and development of meloidogyne incognita in roots of resistant and susceptible corn genotypes. | rates of penetration and development ofmeloidogyne incognita race 4 in roots of resistant (inbred mp307, and s4 lines derived from the open-pollinated varieties tebeau and old raccoon) and susceptible (pioneer 3110) corn genotypes were determined. seedlings grown in styrofoam containers were inoculated with 5,000 eggs of m. incognita. roots were harvested at 3-day intervals starting at 3 days after inoculation (dai) to 27 dai and stained with acid fuchsin. penetration of roots by second-stage ju ... | 1994 | 19279873 |
| effect of crop rotation and tillage on nematode densities in tropical corn. | effects of tillage and crop rotation on nematode densities in tropical corn (zea mays cv. pioneer x304c) were examined in a factorial experiment with two rotation crops and two tillage practices (no-till vs. conventional-till), conducted in each of three seasons (1990-1992) in north florida. the rotation treatments consisted of sorghum (sorghum bicolor cv. dekalb br64) or soybean (glycine max) grown during the 1989 season. densities of meloidogyne incognita (race 1) remained lower throughout the ... | 1993 | 19279846 |
| colonization of greenhouse nematode cultures by nematophagous mites and fungi. | unproductive > 7-year-old greenhouse cultures of citrus nematode (tylenchulus semipenetrans) had a well-developed soil invertebrate fauna that included nematophagous mite species characteristic of florida citrus groves. nematophagous mite densities in box cultures were 285 +/- 42 mites/liter, 2.5 to 25 times higher than densities in citrus nematode-infested groves. vigorous root-knot nematode (meloidogyne incognita) cultures grown in steam-pasteurized soil had few nematophagous mites until more ... | 1993 | 19279841 |
| effects of 1,3-dicliloropropene for meloidogyne incognita management on cotton produced under furrow irrigation. | field trials were conducted during 1990 to evaluate the effects of preplant soil fumigation with 1,3-dichloropropene (1,3-d) on yield and fiber quality of furrow-irrigated cotton cultivars subjected to high population densities of meloidogyne incognita. we measured the responses of eight upland cotton cultivars with different levels of root-knot nematode resistance and compared the responses of upland and pima cottons. reductions in lint weight ranged from 10 to 52% among cultivars grown in soil ... | 1993 | 19279835 |
| spatial and temporal interactions of meloidogyne incognita and soybean. | the spatial and temporal dynamics of meloidogyne incognita, relative to soybean shoot and root growth in field microplots, were determined at 11 sampling dates during a growing season. the population dynamics of m. incognita on soybean were dependent on initial population (pi), soil moisture, and root spatial distribution. final egg and juvenile population densities were greatest in plots with higher pi. the population densities of juveniles and eggs were highest from mid- to late-season and wer ... | 1993 | 19279833 |
| 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 |
| response of peach scion cultivars and rootstocks to meloidogyne incognitain vitro and in microplots. | the response of the peach scion cultivars, jerseyqueen, redhaven, compact redhaven, and rio oso gem and rootstocks 'lovely and 'nemaguard' to inoculation with meloidogyne incognita was compared in vitro and in microplots. one or more parameters monitored in vitro correlated with at least one parameter monitored in microplots, 4 years after tree planting (1989). a range of responses was observed from highlysusceptible in lovell to resistant in nemaguard. in vitro and microplot data suggest high a ... | 1993 | 19279797 |
| 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 |
| dynamics of the nuclear complement of giant cells induced by meloidogyne incognita. | the total numbers of nuclei in giant cells induced by meloidogyne incognita in pea, lettuce, tomato, and broad bean were determined. mature giant cells from pea had the most nuclei per giant cell with a mean of 59 +/- 23, lettuce had the fewest with 26 +/- 16, and tomato and broad bean were intermediate. the rate of increase in numbers of nuclei for all plant species was greatest during the first 7 days after inoculation. no mitotic activity was observed in giant cells associated with adult nema ... | 1993 | 19279788 |
| energetics of meloidogyne incognita on resistant and susceptible alyceclover genotypes. | to determine the energy cost of a population of meloidogyne incognita on the roots of alyceclover, nematode biomass was estimated and equations in the literature were used to calculate energy budgets. amounts of energy consumed, respired, or used in production of nematode biomass were calculated. results suggested that severe infestations of root-knot nematodes can remove significant quantities of energy from their hosts. over a 36-day period, a population of 2.6 females of m. incognita per root ... | 1993 | 19279766 |
| characterization of anionic peroxidases in tomato isolines infected by meloidogyne incognita. | changes in peroxidase activity during nematode infection were studied using root extracts of tomato near-isogenic lines differing in resistance to meloidogyne incognita. total peroxidase activity increased slightly in crude extracts of four susceptible isolines but doubled in two resistant lines, monita and motaci. nematode infection enhanced levels of both p-phenylenediamine-pyrocatechol oxidase and syringaldazine oxidase 7 days after inoculation, especially in resistant lines. this elevated pe ... | 1993 | 19279765 |
| recovery and longevity of egg masses of meloidogyne incognita during simulated winter survival. | effects of soil matrix potential on longevity of egg masses of meloidogyne incognita were determined during simulated winter conditions. egg masses were recovered from isolated root fragments incubated in field soil at matrix potentials of -0.1, -0.3, -1.0, and -4.0 bars throughout winter survival periods of 10 weeks for tomato roots and 12 weeks for cotton roots. egg masses were more superficial on cotton roots than on tomato roots and were more easily dislodged from cotton roots during recover ... | 1993 | 19279764 |
| an in vitro test for temperature sensitivity and resistance to meloidogyne incognita in tomato. | an in vitro root explant tissue culture technique is described for determining susceptibility of tomato (lycopersicon esculentum mill.) breeding lines and cultivars to the root-knot nematode meloidogyne incognita. root explants were taken from 2-day-old seedlings cultured for 30 days at 28 c on gamborg's b-5 medium with or without nematode inoculum. the remaining portion of the root and stem from the excised root explants was transferred to soil in pots and grown to maturity in the greenhouse. i ... | 1993 | 19279747 |
| use of nematodes as biomonitors of nonfumigant nematicide movement through field soil. | three field experiments were established in a loamy sand soil in the coastal plain of north carolina to determine downward movement of aldicarb and fenamiphos with a nematode bioassay. penetration of bioassay plant roots by meloidogyne incognita was measured at 1, 3, 7, 14, 21, and 28 days after treatment in the greenhouse as a means of determining nematicide effectiveness. chemical movement was similar in planted and fallow soil. nematicidal activity was greater in soil collected from the 0 to ... | 1993 | 19279744 |
| population development of meloidogyne incognita on soybean defoliated by pseudoplusia includens. | greenhouse studies examined population densities of meloidogyne incognita race 4 on soybean (glycine max 'davis') defoliated by larvae of soybean looper (pseudoplusia indudens (walker)). plants were defoliated over a 2-week period beginning 5 weeks after seedlings were transplanted. four groups of plants were infested with nematodes (5,000 eggs/pot) at 2-week intervals to allow harvesting of plants at 0, 2, 4, and 6 weeks postdefoliation (wpd). plants in each group were harvested 4 weeks after n ... | 1993 | 19279741 |
| inheritance of heat-stable resistance to meloidogyne incognita in lycopersicon peruvianum and its relationship to the mi gene. | the inheritance of heat-stable resistance to the root-knot nematode, meloidogyne incognita (kofoid and white) chitwood, was studied in crosses between different accessions and clones of lycopersicon peruvianum l. f1, f2 and bc1 generations were evaluated for their index of resistance based on numbers of eggs and infective second-stage juveniles (j2) per gram of root, and the segregation ratios were determined in experiments carried out at constant soil temperatures of 25 °c and 30 °c. l. peruvia ... | 1993 | 24196050 |
| the interaction of so2 and root-knot nematode on tomato. | intermittent exposure of tomato plants (cv. pusa ruby) to so(2) at 286 microg m(-3) (3 h every heavy third day for 75 days) induced slight chlorosis of leaves. at 571 microg m(-3), considerable chlorosis with browning developed on the foliage. these symptoms were more pronounced and appeared earlier on so(2)-exposed plants infected with meloidogyne incognita race 1 (mi), especially in post- and concomitant-inoculation exposures. mi and/or so(2) significantly reduced different parameters of plant ... | 1993 | 15091816 |
| differential gene expression in nematode-induced feeding structures of transgenic plants harbouring promoter-gusa fusion constructs. | sedentary plant-parasitic nematodes are able to induce specialized feeding structures in the root system of their host plants by triggering a series of dramatic cellular responses. these changes presumably are accompanied by a reprogramming of gene expression. to monitor such changes, a variety of promoter-gusa fusion constructs were introduced into arabidopsis and tobacco. transgenic plants were analysed histochemically for gus activity in the nematode feeding structures after infection with ei ... | 1993 | 8275103 |
| mitochondrial dna sequence divergence among meloidogyne incognita, romanomermis culicivorax, ascaris suum, and caenorhabditis elegans. | mitochondrial dna sequences were obtained from the nadh dehydrogenase subunit 3 (nd3), large rrna, and cytochrome b genes from meloidogyne incognita and romanomermis culicivorax. both species show considerable genetic distance within these same genes when compared with caenorhabditis elegans or ascaris suum, two species previously analyzed. caenorhabditis, ascaris, and meloidogyne were selected as representatives of three subclasses in the nematode class secernentea: rhabditia, spiruria, and dip ... | 1993 | 19279810 |
| differential sensitivity of meloidogyne spp. and heterodera glycines to selected nematicides. | differential sensitivity of meloidogyne arenaria, m. hapla, m. incognita, m. javanica, and heterodera glycines races 1 and 5 to the nonfumigant nematicides aldicarb, ethoprop, and fenamiphos was evaluated using a 48-hour root-penetration bioassay. generally, h. glycines was more tolerant of the nematicides, especially ethoprop, than were the meloidogyne species. among meloidogyne species, m. incognita was most sensitive to aldicarb and fenamiphos, but its reaction to ethoprop was similar to the ... | 1993 | 19279834 |
| reduction of phytoparasitic nematodes on tomato by soil solarization and genotype. | the effects of soil solarization and tomato (lycopersicon esculentum) genotype on populations of plant-parasitic nematodes and bacterial wilt were examined in north florida. maximum soil temperatures achieved under solarization treatments using a photoselective polyethylene mulch were 49.5, 46, and 40.5 c at depths of 5, 15, and 25 cm, respectively. soil solarization reduced (p < 0.05) populations of paratrichodorus minor, rotylenchulus reniformis, and criconemella spp. 85 days after transplanti ... | 1993 | 19279843 |
| reproduction of plant-parasitic nematodes on winter rapeseed (brassica napus ssp. oleiferas). | the reproduction of isolates of five plant-parasitic nematode species on the winter rapeseed cultivars bridger, gorzanski, h-47, lindora, and viking was evaluated. each cultivar was a good host for helicotylenchus pseudorobustus, meloidogyne hapla, and m. incognita, all rapeseed cultivars were poor hosts for pratylenchus scribneri, in comparison with a susceptible reference host. heterodera glycines females rarely developed on any cultivar, but low numbers of juveniles invaded roots and males oc ... | 1993 | 19279854 |
| response of trifolium repens clones to infection by meloidogyne incognita and peanut stunt virus. | the responses of selected clones of white clover (trifolium repens) to simultaneous infection by the southern root-knot nematode (meloidogyne incognita) and peanut stunt virus (psv) were determined. two white clover clones, which were resistant (nc-r) or sensitive (nc-s) to ozone injury, were evaluated. plant growth and m. incognita reproduction were measured. root, stolon, and top growth were reduced by psv infection, which affected nc-r more than nc-s. both clones were tolerant of m. incognita ... | 1993 | 19279855 |
| meloidogyne incognita and rotylenchulus reniformis and associated soil textures from some cotton production areas of texas. | the incidence of meloidogyne incognita and rotylenchulus reniformis on cotton was determined in 1989-92 from 1,089 soil samples collected from 31 counties that account for nearly 60% of the 2.2 million hectares planted to cotton in texas. meloidogyne incognita was commonly found in the southern high plains and brazos river valley regions of texas (57% and 34%, respectively, of samples) but was found in less than 8% of samples from the central blacklands, coastal bend, low plains, or the upper gu ... | 1993 | 19279860 |
| host suitability of graminaceous crop cultivars for isolates of meloidogyne arenaria and m. incognita. | twenty-two graminaceous plant cultivars were evaluated in the greenhouse for host suitability for three south carolina isolates of meloidogyne arenaria race 2 (ma-r2) designated as florence, govan, and pelion, a florida isolate of m. arenaria race 1 (ma-r1), and a south carolina m. incognita race 3. host suitability was determined by calculating egg mass index (emi) reproduction factor (rf) (final egg numbers/initial egg numbers), and number of eggs per gram fresh root. corn hybrids pioneer 3147 ... | 1993 | 19279853 |
| a polymerase chain reaction method for identification of five major meloidogyne species. | a polymerase chain reaction (pcr) method for discriminating meloidogyne incognita, m. arenaria, m. javanica, m. hapla, and m. chitwoodi was developed. single juveniles were ruptured in a drop of water and added directly to a pcr reaction mixture in a microcentrifuge tube. primer annealing sites were located in the 3' portion of the mitochondrial gene coding for cytochrome oxidase subunit ii and in the 16s rrna gene. following pcr amplification, fragments of three sizes were detected. the m. inco ... | 1993 | 19279734 |
| effects of root decay on the relationship between meloidogyne spp. gall index and egg mass number in cucumber and horned cucumber. | a greenhouse study was conducted to determine if root necrosis had an effect on the relationship between root-knot nematode gall index and egg mass number. thirty-four cultigens of cucumis (14 accessions, 12 cultivars, and six breeding lines of c. sativus, and two accessions of c. metuliferus) were evaluated against four root-knot species (meloidogyne arenaria race 2, m. incognita race 1, m. incognita race 3, and m. javanica) measuring gall index, root necrosis, and egg mass number. root necrosi ... | 1992 | 19283049 |
| parasitism of helicotylenchus lobus by pasteuria penetrans in naturally infested soil. | the population density of helicotylenchus lobus and the percentage of the population with spores of pasteuria penetrans were determined for 10 monthly intervals in naturally infested turf grass soil at riverside, california. the percentage of nematodes with attached spores ranged from 40% to 67%. no relationship was found between nematode density and the percentage of nematodes with spores. the mean and maximum numbers of spores adhering per nematode with at least one spore ranged from 2 to 8 an ... | 1992 | 19283198 |
| evaluation of nicotiana otophora as a source of resistance to meloidogyne incognita race 4 for tobacco. | no currently available tobacco cultivar possesses resistance to meloidogyne incognita race 4, nor has any source of resistance been reported within nicotiana tabacum. the purpose of this study was to evaluate n. otophora acc. la quinta as a source of resistance to this pathogen. plants of tobacco cvs. nc 95 and nc 2326, n. otophora la quinta and n. repanda were inoculated with second-stage juveniles of m. incognita race 4. gall indices and egg-mass ratings were assessed at 4 and 8 weeks after in ... | 1992 | 19282991 |
| comparison of reproduction by meloidogyne graminicola and m. incognita on trifolium species. | the reproductive potential of meloidogyne graminicola was compared with that of m. incognita on trifolium species in greenhouse studies. twenty-five trifolium plant introductions, cultivars, or populations representing 23 species were evaluated for nematode reproduction and root galling 45 days after inoculation with 3,000 eggs of m. graminicola or m. incognita. root galling and egg production by the two root-knot nematode species was similar on most of the trifolium species. in a separate study ... | 1992 | 19282992 |
| effect of temperature on attachment, development, and interactions of pasteuria penetrans on meloidogyne incognita. | the effect of temperature (10, 20, 25, 30, and 35 c) on attachment and development of pasteuria penetrans on meloidogyne arenaria race 1 was elevated in growth chambers. the greatest attachment rate of endospores of p. penetrans occurred on second-stage juveniles at 30 c. the bacterium developed more quickly within its host at 30 and 35 c than at 25 c or below. the development of the bacterium within the nematode female was divided into nine recognizable life stages, which ranged from early vege ... | 1992 | 19283029 |
| crop rotation studies with velvetbean (mucuna deeringiana) for the management of meloidogyne spp. | results from a greenhouse experiment at cabrils, spain, with two velvetbean (mucuna deeringiana) accessions (florida and mozambique) growing in sterilized sandy loam and inoculated with meloidogyne arenaria race 2, m. incognita race 1, and m. javanica revealed that the legume was not a host for these nematodes. in contrast, roots of 'clemson spineless' okra (hibiscus esculentum), 'summer crookneck' squash (cucurbita pepo), and 'davis' soybean (glycine max) were galled by all three root-knot nema ... | 1992 | 19283043 |
| management of plant-parasitic nematodes with a chitin-urea soil amendment and other materials. | field trials were conducted with a chitin-urea soil amendment and several other nematicides on four crop-nematode combinations: tomato-meloidogyne incognita; potato-meloidogyne chitwoodi; walnut-pratylenchus vulnus; and brussels sprouts-heterodera schachtii. significant (p </= 0.10) nematode population reductions were obtained with the chitin-urea soil amendment in the trims on potato and walnut. in the trials on brussels sprouts and on tomato, phytotoxicity occurred at rates of 1,868 and 1,093 ... | 1992 | 19283044 |
| reproduction of four races of meloidogyne incognita on hibiscus cannabinus. | the feasibility of cultivation of kenaf (hibiscus cannabinus) in the united states is receiving a multifaceted evaluation. among the factors being evaluated is kenafs susceptibility to nematodes. in this investigation, four races of meloidogyne incognita reproduced extensively on each of the several kenaf genotypes examined in greenhouse tests. some genotypes of kenaf, however, demonstrated limited resistance to certain races of m. incognita. | 1992 | 19283051 |
| survey of nematodes on coffee in hawaii. | surveys of coffee fields in hawaii during 1989-1991 indicated the presence of 10 nematode species in 8 genera. after coffee was planted in fields previously in sugarcane, populations of criconemella sp. and pratylenchus zeae gradually decreased, while rotylenchulus reniformis and, in one field, meloidogyne incognita, increased in numbers. coffee is a poor host of r. reniformis, but weeds in coffee plantations may support this nematode. at present, nematodes pose no serious threat to hawaii's exp ... | 1992 | 19283060 |
| survey of plant-parasitic nematodes in missouri cotton fields. | during september 1990, 30 cotton fields in each of three missouri counties were surveyed for plant-parasitic nematodes. soil samples for nematode analysis consisted of a composite of 20 cores collected in a zig-zag pattern within a 1-ha block in each field. cores were taken from within weed-free cotton rows. nine genera of plant-parasitic nematodes were found (rotylenchulus, helicotylenchus, hoplolaimus, meloidogyne, paratylenchus, pratylenchus, tylenchorhynchus, heterodera, and trichodorus), an ... | 1992 | 19283062 |
| occurrence of meloidogyne spp. in argentina. | a record of 84 plant species in 32 families that are hosts to the root-knot nematode species found in argentina is presented. the genus meloidogyne appears to be widely distributed in the country, with meloidogyne incognita and m. javanica the most frequently detected species. other species found in argentina include m. arenaria, m. cruciani, m. decalineata, m. hapla, and m. ottersoni. the present survey is supplemented with existing published information. | 1992 | 19283059 |
| host suitability of ixora spp. for the root-knot nematodes meloidogyne incognita race 1 and m. javanica. | eight commonly cultivated ixora species or cultivars were tested for their suitability as hosts and their level of tolerance to meloidogyne incognita race 1 and m. javanica in a greenhouse study. twenty weeks postinoculation with 5,000 eggs per pot, m. incognita race 1 and m. javanica produced galls and formed egg masses on roots of all eight ixora species or cultivars tested. however, only m. javanica-infected 'petite yellow' and 'maui' had decreases (p </= 0.05) in root wet weights, suggesting ... | 1992 | 19283052 |
| 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 |
| establishment of orchards with black polyethylene film mulching: effect on nematode and fungal pathogens, water conservation, and tree growth. | placement of a 3-m-wide, black, polyethylene film mulch down rows of peach (prunus persica 'red haven' on 'lovell' rootstock) and almond (prunus dulcis 'nonpareil' on 'lovell') trees in the san joaquin valley of california resulted in irrigation water conservation of 75%, higher soil temperature in the surface 30 cm, a tendency toward greater root mass, elimination of weeds, and a greater abundance of meloidogyne incognita second-stage juveniles in soil but reduced root galling when compared to ... | 1992 | 19283045 |
| nematode numbers and crop yield in a fenamiphos-treated sweet corn-sweet potato-vetch cropping system. | nematode population densities and yield of sweet corn and sweet potato as affected by the nematicide fenamiphos, in a sweet corn-sweet potato-vetch cropping system, were determined in a 5-year test (1981-85). sweet potato was the best host of meloidogyne incognita of these three crops. fenamiphos 15g (6.7 kg a.i./ha) incorporated broadcast in the top 15 cm of the soil layer before planting of each crop increased (p </= 0.05) yields of sweet corn in 1981 and 1982 and sweet potato number 1 grade i ... | 1992 | 19283032 |
| inheritance of resistance to meloidogyne spp. in common bean and the genetic basis of its sensitivity to temperature. | bean lines pi 165426, pi 165435, and alabama no. 1, possessing resistance to meloidogyne incognita, and bean lines a315 and a445, possessing gene me1, were tested against several meloidogyne incognita and m. javanica isolates. resistance in bean line pi 165426, pi 165435, and alabama no. 1 was found to be complementary to resistance conferred by gene me1. resistance in pi 165426 was found to be dominant and conditioned by one dominant and one recessive gene at 26 °c. we propose me2me3 as the gen ... | 1992 | 24202746 |
| effects of rapeseed and vetch as green manure crops and fallow on nematodes and soil-borne pathogens. | in a rapeseed-squash cropping system, meloidogyne incognita race 1 and m. javanica did not enter, feed, or reproduce in roots of seven rapeseed cultivars. both nematode species reproduced at low levels on roots of the third crop of rapeseed. reproduction of m. incognita and m. javanica was high on squash following rapeseed, hairy vetch, and fallow. the application of fenamiphos suppressed (p = 0.05) root-gall indices on squash following rapeseed, hairy vetch, and fallow; and on dwarf essex and c ... | 1992 | 19283212 |
| counting nematodes with a microplate reader. | the feasibility of counting plant-parasitic nematodes in aqueous suspensions by measuring light transmittance through aqueous suspensions with an elisa microplate reader was explored. absorbance readings for eggs or vermiform stages of three species were linearly related (r(2) > 0.99) to concentrations between 0 and 10,000 nematodes/ml. coefficients of variation ranged from 12-23%, depending on the species and developmental stage used. the method, therefore, was at least as accurate as direct co ... | 1992 | 19283207 |
| invasion of tomato roots and reproduction of meloidogyne incognita as affected by raw sewage sludge. | the antagonistic effects of raw sewage sludge on infection of tomato by meloidogyne incognita were tested in greenhouse pot experiments. sludge was mixed with the soil or added on its surface before and after inoculation of tomato plants with nematode eggs. juvenile penetration was determined 1 and 10 days after inoculation, and 6 weeks later root systems were assessed for nematode reproduction. fewer juveniles penetrated roots in pots with sludge added to the soil than in unamended control pots ... | 1991 | 19283192 |
| nematode population changes and forage yields of six corn and sorghum cultivars. | two temperate corn (zea mays) hybrids (pioneer 3320 and northrup king 508), two tropical corn cultivars (pioneer x304c hybrid and florida syn-1 experimental open pollinated cultivar), the sorghum (sorghum bicolor) x sudangrass (sorghum sudanense) hybrid dekalb sx-17, and the sorghum hybrid dekalb fs25e were compared for effect on nematode densities and forage yield in three plantings (one single-crop and one double-crop system) in florida. final population densities of meloidogyne incognita in t ... | 1991 | 19283183 |
| 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 |
| response of tomato cultigens to meloidogyne javanica and races of meloidogyne incognita. | thirty-six cultigens of tomato were evaluated for resistance against meloidogyne javanica and four races of m. incognita with standards and parameters adopted by the international meloidogyne project. most cultigens were susceptible to the nematodes, including some that were previously reported to be resistant to these nematodes. ten accessions, namely pusa-120, calmart vfn, panjab 6.nr-7, ec173898 (72t6), ec173897 (cal-mart), ec173896 (kewalo), cln363bcf-167-1-0, cln363bcf-190-1-0, cln363bcf-34 ... | 1991 | 19283169 |
| reaction of trifolium repens cultivars and germplasms to meloidogyne incognita. | ten cultivars and 13 germplasms of white clover (trifolium repens) were evaluated in the greenhouse for resistance to the southern root-knot nematode, meloidogyne incognita race 4. one hundred plants of each cultivar or germplasm were rated for percentage of the root system galled (prsg) at 60 days after inoculation with root-knot nematode eggs. tillman (9%) and srvr (19%) had the highest percentage of resistant plants (prsg = 0 or 1 on a scale of 0-5 ) for the cultivars and germplasms, respecti ... | 1991 | 19283168 |
| interaction of meloidogyne incognita and water stress in two cotton cultivars. | a series of controlled-environment experiments were conducted to elucidate the effects of meloidogyne incognita on host physiology and plant-water relations of two cotton (gossypium hirsutum) cultivars that differed in their susceptibility to nematode infection. inoculation of m. incognita-resistant cultivar auburn 634 did not affect growth, stomatal resistance, or components of plant-water potential relative to uninoculated controls. however, nematode infection of the susceptible cultivar stone ... | 1991 | 19283156 |
| infection of cultured thin cell layer roots of lycopersicon esculentum by meloidogyne incognita. | a new aseptic culture system for studying interactions between tomato (lycopersicon esculentum) and meloidogyne incognita is described. epidermal thin cell layer explants from peduncles of tomato produced up to 20 adventitious roots per culture in 4-9 days on murashige &scoog medium plus kinetin and indole acetic acid. rooted cultures were transferred to gamborg's b-5 medium and inoculated with infective second-stage juveniles. gall formation was apparent 5 days after inoculation and egg product ... | 1991 | 19283152 |
| evidence against amplification of four genes in giant cells induced by meloidogyne incognita. | giant-cell dna was isolated from pea (pisum sativum) inoculated with meloidogyne incognita and used in slot blots to test for selective sequence amplification. four sequences representing low (ribulose 1,5-bisphosphate carboxylase and actin), mid-level (histone 3), and highly repetitive (large ribosomal repeat) sequence dna were used as probes. known amounts of root-tip dna and giant-cell dna were blotted onto hybridization membranes and probed. the signal strength on autoradiographs containing ... | 1991 | 19283148 |
| plant protection with inorganic ions. | gradients of salts of the specific ion repellents for meloidogyne incognita -- nh, k, cl, and no -- have been demonstrated to shield tomato roots from infestation in soil. the strategy of these greenhouse experiments was to interpose a salt barrier in a soil column between the plant roots and the nematodes. the relative effectiveness of the salts as a barrier to infective second-stage juveniles in a sandy loam was nhno, nhcl > kno > kcl. some of these ions are beneficial to plant growth, and the ... | 1991 | 19283146 |
| isolation of a repeated dna probe showing polymorphism among meloidogyne incognita populations. | several meloidogyne incognita geographic populations were characterized by analysis of the restriction fragment length polymorphisms (rflp) obtained after digestion of their total dna and hybridization with a [(3)(2)p]-labeled probe. the probe consisted of a 1.7-kb-repeated dna sequence, isolated from a m. incognita genomic library, that hybridized to multiple bamh i fragments in the genome of each isolate. the patterns showed sufficient polymorphism to enable the accurate differentiation of all ... | 1991 | 19283132 |
| interaction of meloidogyne javanica with different races of meloidogyne incognita. | the interspecific interactions of meloidogyne javanica with races 1, 2, 3, and 4 of m. incognita on tomato were determined. impacts of the interactions on fecundity and morphometrics of females were also examined. mutually inhibitory interactions occurred between m. javanica and the races of m. incognita, but the negative interactions did not reflect in plant growth. numbers of root galls, egg masses, mature females, total population, fecundity, and reproduction factor declined in concomitant tr ... | 1991 | 19283130 |
| biomass partitioning in tomato plants infected with meloidogyne incognita. | tomato plants were inoculated with meloidogyne incognita at initial populations (pi) of 0, 1, 10, 50, 100, and 200 (x 1,000) eggs per plant and maintained in a growth chamber for 40 days. total fresh biomass (roots + shoots) at harvest was unchanged by nematode inoculation with pi of 1 x 10 eggs or less. reductions in fresh shoot weight with increasing pi coincided with increases in root weight. total fresh biomass declined with pi above 1 x 10 eggs, whereas total dry biomass declined at pi abov ... | 1991 | 19283129 |
| induction of isoperoxidases in resistant and susceptible tomato cultivars by meloidogyne incognita. | isoperoxidases were detected in resistant rossol and susceptible roma vf tomato roots uninfected and infected by meloidogyne incognita. syringaldazine, guaiacol, p-phenylenediamine-pyrocatechol (ppd-pc), and indoleacetic acid (iaa) were used as substrates, and the corresponding peroxidative activities were detected either in cytoplasmic or in cell wall fractions, except for iaa oxidase, which was measured in soluble and microsomal fractions. isoperoxidase activities and cellular locations were i ... | 1991 | 19283122 |
| modification of resistance expression of phaseolus vulgaris to meloidogyne incognita by elevated soil temperatures. | the effect of temperature on the reaction of susceptible (canario divex) and resistant (a 211) bean pure lines to meloidogyne incognita was studied with soil temperature tanks housed in a growth chamber at 22 or 24 c. soil temperature remained constant at 16, 22, 24, 26, 30, or 32 c in several trials. bean line a 211 was resistant at 16 and 22 c but was susceptible at 24 c and above. resistance to root-knot nematode reproduction was affected by a lower temperature (24 c) than was resistance to r ... | 1991 | 19283110 |
| penetration and development of meloidogyne incognita on roots of resistant soybean genotypes. | meloidogyne incognita penetration and development were studied in roots of highly resistant (pi 96354, pi 417444), resistant (forrest), and susceptible (bossier) soybean genotypes. although more second-stage juveniles (j2) had penetrated roots of pi 96354 and pi 417444 than roots of forrest and bossier by 2 days after inoculation, fewer j2 were present in roots of pi 96354 at 4 days after inoculation. juvenile development in all genotypes was evident by 6 days after inoculation, with the highest ... | 1991 | 19283106 |
| relationships between soil and levels of meloidogyne incognita and tobacco yield and quality. | a 2-year study with six soils and four levels of meloidogyne incognita in microplots was designed to determine the effects of these parameters on nematode activity and tobacco yield and quality. key components under study were affected by soil, nematode level, and season (year-cultivar). in 1980, low initial nematode numbers (1,250) enhanced tobacco yield in cecil clay loam, but caused slight to moderate yield losses in the other soils. yield losses to m. incognita were generally greatest in san ... | 1991 | 19283097 |
| biological control of soil pests by mixed application of entomopathogenic and fungivorous nematodes. | in greenhouse experiments, massive application of the fungivorous nematode, aphelenchus avenae, in summer at 26-33 c (1 x l0 nematodes/500 cm(3) autoclaved soil) or in autumn at 18-23 c (5 x 10 nematodes/500 cm(3) autoclaved soil) suppressed pre-emergence damping-off of cucumber seedlings due to rhizoctonia solani ag-4 by 67% or 87%, respectively. application of 2 x l0 a. avenae to sterilized soil infested with r. solani caused leafminer-like symptom on the cotyledons, which did not occur in mix ... | 1991 | 19283109 |
| penetration of susceptible and resistant tobacco cultivars by meloidogyne juveniles. | rates of penetration of meloidogyne incognita, m. arenaria, and m. javanica into tobacco cultivars nc2326 (susceptible to all three species) and k399 (resistant to m. incognita) and a breeding line that had been selected for resistance to m. incognita were compared. meloidogyne incognita penetrated nc2326 rapidly during the first 24 hours after inoculation. numbers of m. incognita continued to increase gradually through the 14-day experiment. higher numbers of m. incognita were observed in the r ... | 1991 | 19283116 |
| interaction between meloidogyne incognita and agrobacterium tumefaciens or fusarium oxysporum f. sp. lycopersici on tomato. | agrobacterium tumefaciens stimulated and fusarium oxysporum f. sp. lycopersici inhibited development and reproduction of meloidogyne incognita when applied to the opposite split root of tomato, lycopersicon esculentum cv. tropic, plants. the lowest rate of nematode reproduction occurred after 2,000 juveniles were applied and the fungus was present in the opposite split root. the effects of all three pathogens alone on the growth of roots and shoots of tomato plants were evident, but m. incognita ... | 1991 | 19283119 |
| stage-specific differences in lectin binding to the surface of anguina tritici and meloidogyne incognita. | the occurrence and distribution of several lectin binding sites on the outer surfaces of eggs, preparasitic second-stage juveniles (j2), parasitic second-stage juveniles (pj2), females, and males of two tylenchid nematodes, anguina tritici and meloidogyne incognita race 3, were compared. in both species, a greater variety of lectins bound to the eggs than to other life stages; lectin binding to eggs was also more intense than it was to other life stages. species-specific differences also occurre ... | 1991 | 19283123 |
| characteristics and efficacy of a sterile hyphomycete (arf18), a new biocontrol agent for heterodera glycines and other nematodes. | a filamentous, nonsporulating fungus, designated arkansas fungus 18 (arf18), was isolated from 9 of 95 populations of heterodera glycines, the soybean cyst nematode, in arkansas. in petri dishes, arf18 parasitized 89% of h. glycines eggs in cysts. the fungus also infected eggs of meloidogyne incognita and eggs in cysts of cactodera betulae, h. graminophila, h. lespedezae, h. leuceilyma, h. schachtii, and h. trifolii. in pot tests, reproduction of scn was 70% less in untreated field soil that was ... | 1991 | 19283127 |
| yield-loss models for tobacco infected with meloidogyne incognita as affected by soil moisture. | yield-loss models were developed for tobacco infected with meloidogyne incognita grown in microplots under various irrigation regimes. the rate of relative yield loss per initial nematode density (pi), where relative yield is a proportion of the value of the harvested leaves in uninfected plants with the same irrigation treatment, was greater under conditions of water stress or with high irrigation than at an intermediate level of soil moisture. the maximum rate of plant growth per degree-day (b ... | 1991 | 19283140 |
| resistance in soybean cultivars from maturity groups v-viii to soybean cyst and root-knot nematodes. | one hundred thirty-nine cultivars of soybean (glycine max) in maturity groups v, vi, vii, and viii were evaluated in a greenhouse for resistance to heterodera glycines races 3 and 14 and meloidogyne incognita, m. arenaria, and m. javanica. of the cultivars tested, 37% had resistance to h. glycines race 3 alone, 12% had resistance to both races 3 and 14, and 69% exhibited a moderate or high level of resistance to one or more of the meloidogyne spp. however, 24% were susceptible to each race of h. ... | 1991 | 19283166 |
| a species-specific oligonucleotide dna probe for the identification of meloidogyne incognita. | a genomic library of meloidogyne incognita race 1 has been prepared in the bacteriophage lambda gt10 and screened for specific dna sequences by hybridization with radio-isotope labelled total genomic dna from a number of meloidogyne species. one clone isolated (mr1 #15), although not totally species specific, clearly showed preferential hybridization to m. incognita. following subcloning and sequencing of the 255 bp insert, four stretches of the sequence corresponding to oligonucleotides of appr ... | 1991 | 1745557 |