| natural dehydration regimes as a prerequisite for the successful induction of anhydrobiosis in the nematode rotylenchulus reniformis. | induction of anhydrobiosis in the nematode rotylenchulus reniformis (linford & oliveira) was studied using direct exposure to elevated relative humidities and conditions resembling natural dehydration regimes. all larvae and preadults were unable to survive direct short-term exposure to 97% relative humidity. however, dehydration of larvae on model substrates (0.5% agar: 1.0% agarose) that mimic the natural rate of soil moisture loss induced coiling and successful entry into anhydrobiosis. coili ... | 1989 | 2732663 |
| responses of the plant parasitic nematodes rotylenchulus reniformis, anguina agrostis and meloidogyne javanica to chemical attractants. | rotylenchulus reniformis, anguina agrostis and meloidogyne javanica respond differently to gradients of chemical attractants. in chemotaxis assays performed on agarose plates, r. reniformis l2 larvae oriented their movement to several common inorganic salts, cyclic amp and amp, as well as to germinated host plant seeds. m. javanica l2 larvae were attracted to germinated seeds, but not to the salts tested, and a. agrostis dauer larvae were not strongly attracted to any of 12 different tested agen ... | 1985 | 2993986 |
| carbohydrate-recognition domains on the surface of phytophagous nematodes. | human red blood cells (hrbc) adhered to preparasitic second-stage juveniles (j2) of heterodera avenae, heterodera schachtii, meloidogyne javanica, pratylenchus mediterraneus, rotylenchulus reniformis, and tylenchulus semipenetrans over the entire nematode body. binding was conspicuously confined to the head and tail of longidorus cohni, xiphinema brevicolle, and xiphinema index. binding was ca2+ and mg2+ dependent. in contrast, hrbc did not adhere to anguina tritici, aphelenchoides subtenius, di ... | 1995 | 7895833 |
| root-parasitic nematodes enhance soil microbial activities and nitrogen mineralization. | obligate root-parasitic nematodes can affect soil microbes positively by enhancing c and nutrient leakage from roots but negatively by restricting total root growth. however, it is unclear how the resulting changes in c availability affect soil microbial activities and n cycling. in a microplot experiment, effects of root-parasitic reniform nematodes ( rotylenchulus reniformis) on soil microbial biomass and activities were examined in six different soils planted with cotton. rotylenchulus renifo ... | 2003 | 12739076 |
| an efficient method for the purification and characterization of nematicidal azadirachtins a, b, and h, using mplc and esims. | azadirachtin a enriched concentrate containing 60% active ingredient (a.i.) was prepared from the methanolic extract of the de-fatted neem (azadirachta indica a. juss) seed kernels. azadirachtins a, b, and h, the three major bioactive constituents of neem seed kernel, were purified from this methanolic concentrate by employing reverse phase medium-pressure liquid chromatography (mplc), using methanol-water solvent system as an eluant. the three pure azadirachtin congeners thus obtained were char ... | 2003 | 12822931 |
| reniform in u.s. cotton: when, where, why, and some remedies. | the reniform nematode, rotylenchulus reniformis, is an emerging problem in u.s. cotton. the impact of this nematode and the extent to which it has and will continue to spread across the u.s. cotton belt are controversial. long-term changes in cotton production and unique biological attributes of r. reniformis are key factors. expert opinion surveys indicate that r. reniformis has replaced the root-knot nematode (meloidogyne incognita) as the major nematode of cotton in mississippi, louisiana, an ... | 2007 | 17428179 |
| nematicidal prenylated flavanones from phyllanthus niruri. | two prenylated flavanones have been isolated from the hexane extract of phyllanthus niruri plant. the structure of these flavanones were established as 8-(3-methyl-but-2-enyl)-2-phenyl chroman-4-one (1) and 2-(4-hydroxyphenyl)-8-(3-methyl-but-2-enyl)-chroman-4-one (2) on the basis of spectral analysis. these were evaluated for nematicidal activity against root-knot, meloidogyne incognita, and reniform, rotylenchulus reniformis, nematodes. compound 2 exhibited nematicidal activity at par with the ... | 2008 | 17904597 |
| depth distribution of rotylenchulus reniformis under different tillage and crop sequence systems. | abstract the population density of the reniform nematode, rotylenchulus reniformis, was monitored at depths of 0 to 30, 30 to 60, 60 to 90, and 90 to 120 cm in a tillage and crop sequence trial in south texas in 2000 and 2001. main plots were subjected to three different tillage systems: conventional tillage (moldboard plowing and disking), ridge tillage, and no-tillage. subplots were planted with three different crop sequences: spring cotton and fall corn every year; spring cotton and fall corn ... | 2003 | 18944104 |
| isolation, selection, and efficacy of pochonia chlamydosporia for control of rotylenchulus reniformis on cotton. | abstract the reniform nematode, rotylenchulus reniformis, is a serious threat to cotton (gossypium hirsutum) production in the united states, causing an annual loss of about $80 million. the objective of this study was to isolate fungi from eggs of r. reniformis and select potential biocontrol agents for r. reniformis on cotton. we focused on the fungus pochonia chlamydosporia because it suppresses root-knot and cyst nematodes and because preliminary data indicated that it was present in arkansa ... | 2005 | 18944410 |
| suppression of rotylenchulus reniformis 122-cm deep endorses resistance introgression in gossypium. | nine sources of resistance to rotylenchulus reniformis in gossypium (cotton) were tested by measuring population density (pf) and root-length density 0 to 122 cm deep. a pf in the plow layer less than the autumn sample treatment threshold used by consultants was considered the minimum criterion for acceptable resistance, regardless of population density at planting (pi). other criteria were ample roots and a pf lower than on the susceptible control, as in pot studies. in a texas field in 2001 an ... | 2006 | 19259448 |
| sensitivity of meloidogyne incognita and rotylenchulus reniformis to abamectin. | avermectins are macrocyclic lactones produced by streptomyces avermitilis. abamectin is a blend of b(1a) and b(1b) avermectins that is being used as a seed treatment to control plant-parasitic nematodes on cotton and some vegetable crops. no ld(50) values, data on nematode recovery following brief exposure, or effects of sublethal concentrations on infectivity of the plant-parasitic nematodes meloidogyne incognita or rotylenchulus reniformis are available. using an assay of nematode mobility, ld ... | 2006 | 19259453 |
| cotton root protection from plant-parasitic nematodes by abamectin-treated seed. | abamectin is nematicidal to meloidogyne incognita and rotylenchulus reniformis, but the duration and length of cotton taproot protection from nematode infection by abamectin-treated seed is unknown. based on the position of initial root-gall formation along the developing taproot from 21 to 35 d after planting, infection by m. incognita was reduced by abamectin seed treatment. penetration of developing taproots by both nematode species was suppressed at taproot length of 5 cm by abamectin-treate ... | 2007 | 19259471 |
| the future of nematode management in cotton. | the importance of plant-parasitic nematodes as yield-limiting pathogens of cotton has received increased recognition and attention in the united states in the recent past. this paper summarizes the remarks made during a symposium of the same title that was held in july 2007 at the joint meeting of the society of nematologists and the american phytopathological society in san diego, california. although several cultural practices, including crop rotation, can be effective in suppressing the popul ... | 2007 | 19259500 |
| detection of suppressiveness against rotylenchulus reniformis in soil from cotton (gossypium hirsutum) fields in texas and louisiana. | rotylenchulus reniformis is a major problem confronting cotton production in the central part of the cotton belt of the united states of america. in this study, the hypothesis that natural antagonists in some cases are responsible for unusually low densities of the nematode in certain fields was tested by assaying soils from 22 selected fields for the presence of transferable agents in pots containing cotton plants. in one field, soil from four different depth ranges was tested. in the first of ... | 2008 | 19259517 |
| effects of inducers of systemic acquired resistance on reproduction of meloidogyne javanica and rotylenchulus reniformis in pineapple. | the potency of the inducers of systemic acquired resistance (sar), acibenzolar-s-methyl, dl-alpha-amino-n-butyric acid (aaba), dl-beta-amino-n-butyric acid (baba), gamma-amino-n-butyric acid (gaba), p-aminobenzoic acid (paba), riboflavin, and salicylic acid (sa), in reducing reproduction of meloidogyne javanica and rotylenchulus reniformis in pineapple was investigated. all inducers were applied as foliar sprays to 1-mon-old pineapple plants (20 ml/plant) grown in 22-cm-diam. pots in the greenho ... | 2006 | 19259535 |
| comparisons of female and egg assays to identify rotylenchulus reniformis resistance in cotton. | more plants can be screened for reniform nematode resistance each year if the time involved can be shortened. in this study, the hypothesis that female counts are as efficient as egg counts in identifying resistant genotypes was tested. in two greenhouse experiments gossypium genotypes which varied from resistant to susceptible to reniform nematode (rotylenchulus reniformis) were compared to a susceptible control cultivar. infested field soil served as the inoculum source for the first experimen ... | 2006 | 19259536 |
| competition of meloidogyne incognita and rotylenchulus reniformis on cotton following separate and concomitant inoculations. | it has been hypothesized rotylenchulus reniformis (rr) has a competitive advantage over meloidogyne incognita (mi) in the southeastern cotton production region of the united states. this study examines the reproduction and development of meloidogyne incognita (mi) and rotylenchulus reniformis (rr) in separate and concomitant infections on cotton. under greenhouse conditions, cotton seedlings were inoculated simultaneously with juveniles (j2) of m. incognita and vermiform adults of r. reniformis ... | 2003 | 19262774 |
| interaction of rotylenchulus reniformis with seedling disease pathogens of cotton. | the impact of 10 fusarium species in concomitant association with rotylenchulus reniformis on cotton seedling disease was examined under greenhouse conditions. in experiment 1, fungal treatments consisted of fusarium chlamydosporum, f. equiseti, f. lateritium, f. moniliforme, f. oxysporum, f. oxysporum f.sp. vasinfectum, f. proliferatum, f. semitectum, f. solani, and f. sporotrichioides; rhizoctonia solani; and thielaviopsis basicola. the experimental design was a 2 x 14 factorial consisting of ... | 2004 | 19262802 |
| suppression of rotylenchulus reniformis on cotton by the nematophagous fungus arf. | the reniform nematode, rotylenchulus reniformis linford &oliveira, has become a serious threat to cotton (gossypium hirsutum l.) production in the united states during the past decade. the objective of this study is to isolate fungi from eggs of r. reniformis and select potential biological control agents for r. reniformis on cotton. soil samples were collected from cotton fields located in jefferson county, arkansas. eight genera of fungi were included in the 128 fungal isolates obtained, and a ... | 2004 | 19262806 |
| studies on morphological and physio-ecological variations of the reniform nematode, rotylenchulus reniformis linford and oliveira, 1940 with an emphasis on differential geographical distribution of amphimictic and parthenogenetic populations in japan. | the geographical distribution and polymorphism in morphological and biological characters of the reniform nematode, rotylenchulus reniformis, in japan were studied. the northern limit of habitat of this nematode was found on the 14 degrees c isothermal line of annual average-air temperature. three morphologically different groups were ascertained which corresponded to three biological types based on male frequency. incidence of males was consistent within populations and was not affected by envi ... | 2004 | 19262821 |
| intraspecific variability of rotylenchulus reniformis from cotton-growing regions in the united states. | reniform nematode (rotylenchulus reniformis) is a major pest of cotton in the southeastern united states. the objective of this study was to examine the variation of reniform nematode populations from cotton-growing locations in the united states where it is prevalent. multivariate analysis of variance and discriminant analysis were used to determine the variability of morphology in males and immature females. reproduction indices of populations were measured on selected soybean and cotton genot ... | 2005 | 19262849 |
| histological changes in gossypium hirsutum associated with reduced reproduction of rotylenchulus reniformis. | the reniform nematode (rotylenchulus reniformis) is an important parasite of upland cotton (gossypium hirsutum). parasitism involves the formation of syncytia to provide nutrition for the female. events that occur at the feeding site may determine the degree of susceptibility of cotton plants to reniform nematode. the objective of this work was to describe histological modifications associated with reduced reproduction of rotylenchulus reniformis in upland cotton roots. 'deltapine 50' cotton and ... | 2005 | 19262859 |
| vertical distribution of rotylenchulus reniformis in cotton fields. | the possible impact of rotylenchulus reniformis below plow depth was evaluated by measuring the vertical distribution of r. reniformis and soil texture in 20 symptomatic fields on 17 farms across six states. the mean nematode population density per field, 0 to 122 cm deep, ranged from 0.4 to 63 nematodes/g soil, and in 15 fields more than half of the r. reniformis present were below 30.5 cm, which is the greatest depth usually plowed by farmers or sampled by consultants. in 11 fields measured, r ... | 2005 | 19262871 |
| effect of controlled cold storage on recovery of rotylenchulus reniformis from naturally infested soil. | rotylenchulus reniformis is rapidly becoming the most economically important pest associated with cotton in the southeastern united states. incentive programs have been implemented to support sampling of production fields to determine the presence and abundance of r. reniformis. these sampling programs have dramatically increased the number of soils samples submitted to nematology laboratories during autumn. the large numbers of samples overwhelm most labs and require placement in cold storage u ... | 2005 | 19262872 |
| rotylenchulus reniformis below plow depth suppresses cotton yield and root growth. | damage to cotton by rotylenchulus reniformis below plow depth was evaluated in a sandy clay loam soil at weslaco, texas. in december 1999, 14 holes on 51-cm centers were dug 91 cm deep along the planting bed and adjacent furrow and 2 ml of 1,3-dichloropropene was placed 91, 61, and 30 cm deep as each hole was refilled and packed. this technique eliminated 96%, 81%, and 74% of r. reniformis down to 107 cm at distances 0, 25, and 51 cm laterally from the point of application (p </= 0.05), whereas ... | 2005 | 19262875 |
| histological observations of rotylenchulus reniformis on gossypium longicalyx and interspecific cotton hybrids. | observations on the development of reniform nematode (rotylenchulus reniformis) on roots of gossypium longicalyx, g. hirsutum, and two interspecific hybrids derived from them were made by light microscopy. gossypium longicalyx is reported to be immune to reniform nematode, but the mechanism(s) for resistance are unknown. penetration of g. longicalyx roots by female nematodes was confirmed, and incipient swelling of the females, indicating initiation of maturation of the reproductive system, was ... | 2005 | 19262889 |
| plant-parasitic nematodes in the waimanalo, hawaii irrigation system from watershed to farm. | nematode occurrence at specific locations throughout a water catchment-irrigation system was determined. soil samples were collected from five water source locations on the slopes of olomana mountain and maunawili valley and from about 40 plant species on 18 farms (56 ha of 480 ha irrigated by the reservoir). water was sampled from the catchment reservoir at 0.3 m, 9 m, and 18 m (bottom). a farm irrigated with potable water was sampled and compared to areas of the same farm irrigated from the re ... | 2001 | 19265890 |
| management of root-knot and reniform nematodes in ultra-narrow row cotton with 1,3-dichloropropene. | ultra-narrow row cotton studies were conducted during 1999 at two field sites in northern florida. one site was naturally infested with meloidogyne incognita race 3 and the other with rotylenchulus reniformis. the fumigant 1,3-dichloropropene (1,3-d) was applied broadcast at rates of 0, 16, 32, 48, 64, 80, and 96 kg ai./ha in replicated plots before planting delta pine 655 brr cotton in 25-cm-wide rows. post-harvest soil population densities at the root-knot nematode site had a significant (p </ ... | 2001 | 19265894 |
| host suitability in soybean cultivars for the reniform nematode, 2000 tests. | in greenhouse pot experiments during summer 2000, 118 soybean cultivars were tested to determine their suitability as hosts for the reniform nematode, rotylenchulus reniformis. the cultivars included 115 new entries into the arkansas and mississippi soybean variety testing programs and three entries submitted by an extension nematologist from texas. also included in the tests were the r. reniformis-resistant cultivars forrest and hartwig, the susceptible cultivar braxton, and fallow r. reniformi ... | 2001 | 19265895 |
| management of rotylenchulus reniformis in pineapple, ananas comosus, by intercycle cover crops. | the effects of intercycle cover crops on rotylenchulus reniformis population densities in pineapple were evaluated in one greenhouse and two field experiments. in the greenhouse, crotalaria juncea, brassica napus, and tagetes erecta were planted for 3 months and then incorporated. these treatments were compared to weedy fallow with or without 1,3-dichloropropene (1,3-d) in three soils (makawao fallow, wahiawa fallow, and wahiawa pineapple) naturally infested with r. reniformis. all cover crop in ... | 2002 | 19265916 |
| using geostatistical analysis to evaluate the presence of rotylenchulus reniformis in cotton crops in brazil: economic implications. | in recent years, the productivity of cotton in brazil has been progressively decreasing, often the result of the reniform nematode rotylenchulus reniformis. this species can reduce crop productivity by up to 40%. nematodes can be controlled by nematicides but, because of expense and toxicity, application of nematicides to large crop areas may be undesirable. in this work, a methodology using geostatistics for quantifying the risk of nematicide application to small crop areas is proposed. this ri ... | 2002 | 19265938 |
| host suitability of soybean cultivars and breeding lines to reniform nematode in tests conducted in 2001. | reproduction of reniform nematode rotylenchulus reniformis on 139 soybean lines was evaluated in a greenhouse in the summer of 2001. cultivars and lines (119 total) were new in the arkansas and mississippi soybean testing programs, and an additional 20 were submitted by c. overstreet, louisiana state extension nematologist. a second test of 32 breeding lines and 2 cultivars from the clemson university soybean breeding program was performed at the same time under the same conditions. controls wer ... | 2002 | 19265960 |
| intercropping cover crops with pineapple for the management of rotylenchulus reniformis. | effect of cover crops intercropped with pineapple (ananas comosus) on rotylenchulus reniformis population densities and activity of nematode-trapping fungi (ntf) were evaluated in two cycles of cover crop and pineapple. sunn hemp (crotalaria juncea), rapeseed (brassica napus), african marigold (tagetes erecta), or weeds were intercropped with pineapples. beds planted with sunn hemp or rapeseed had lower population densities of r. reniformis than african marigold, weeds, or pineapple plots during ... | 2003 | 19265973 |
| rotylenchulus reniformis management in cotton with crop rotation. | one-year crop rotations with corn or highly resistant soybean were evaluated at four locations for their effect on rotylenchulus reniformis population levels and yield of a subsequent cotton crop. four nematicide (aldicarb) regimes were included at two of the locations, and rotation with reniform-susceptible soybean was included at the other two locations. one-year rotations to corn or resistant soybean resulted in lower r. reniformis population levels (p </= 0.05) than those found in cotton at ... | 2003 | 19265975 |
| efficacy of aldicarb to rotylenchulus reniformis and biodegradation in cotton field soils. | the microbial degradation of aldicarb was examined in the greenhouse using soil from four cotton fields with a history of aldicarb use. the addition of aldicarb at 0.59 kg a.i./ha to natural soil increased rotylenchulus reniformis numbers 6.6% in one soil and decreased r. reniformis numbers only 25.8% in another soil as compared to the corresponding natural soil without aldicarb. the use of increasing rates of aldicarb did not increase the efficacy of aldicarb in these soils. rotylenchulus renif ... | 2003 | 19265976 |
| effects of acibenzolar-s-methyl application to rotylenchulus reniformis and meloidogyne javanica. | effects of acibenzolar-s-methyl, an inducer of systemic acquired resistance in plants, on rotylenchulus reniformis and meloidogyne javanica in vitro and in vivo were determined. a single foliar application of acibenzolar at 50 mg/liter (5 ml of solution per plant) to 7-day-old cowpea or soybean seedlings decreased r. reniformis and m. javanica egg production by 50% 30 days after inoculation. the mechanism of acibenzolar on plant-parasitic nematodes was then investigated. acibenzolar at 50 to 200 ... | 2003 | 19265983 |
| 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 |
| reniform nematode resistance in selected soybean cultivars. | two hundred eighty-two soybean cultivars from the variety testing programs of arkansas and mississippi were tested in greenhouse pot experiments during summer 1998 to identify soybean cultivars with resistance to the reniform nematode, rotylenchulus reniformis. also included in the tests were the resistant cultivars forrest and hartwig, the susceptible control braxton, and fallow infested soil, which were used as controls. numbers of reniform nematode extracted from the soil and roots and the ra ... | 1999 | 19270934 |
| a survey of plant-parasitic nematodes associated with cotton in northeastern louisiana. | a survey was conducted in northeastern louisiana to determine the frequency and abundance of plant-parasitic nematodes associated with cotton. in fall 1997 and 1998, more than 600 soil samples were collected from cotton fields representing 6,200 ha, which is 5.3% of the cotton production hectarage in this region. composite soil samples were collected from 10 ha in each field. nematodes were extracted by gravity screening and sucrose centrifugation, identified to genus, and quantified. nine gener ... | 2000 | 19271002 |
| tolerance of selected cotton lines to rotylenchulus reniformis. | the reproductive and damage potential of the reniform nematode, rotylenchulus reniformis, on five cotton breeding lines reported as tolerant to this nematode in texas were compared with two standard cotton cultivars, deltapine 50 and stoneville la 887, in a north carolina field naturally infested with r. reniformis. numbers of r. reniformis in soil were suppressed at mid-season, and cotton-lint yield was increased by preplant fumigation with 1,3-dichloropropene. population densities of r. renifo ... | 2000 | 19271004 |
| effect of foliar applications of oxamyl with aldicarb for the management of rotylenchulus reniformison cotton. | the efficacy of foliar applications of oxamyl were evaluated for the management of rotylenchulus reniformis on cotton in mississippi. two tests were established in tallahatchie county on a fine sandy loam soil (56.8% sand, 37.8% silt, 5.3% clay, ph 5.4, and 0.3% om) naturally infested with r. reniformis. oxamyl was applied as a foliar spray at 0.14, 0.27, or 0.53 kg a.i./ha to cotton plants that had reached the sixth true leaf growth stage. a second oxamyl application was applied 14 days after t ... | 2000 | 19271008 |
| host suitability in soybean cultivars for the reniform nematode, 1999 tests. | two hundred twenty-six soybean cultivars were tested in greenhouse pot experiments during summer 1999 to determine their suitability as hosts for the reniform nematode, rotylenchulus reniformis. the cultivars included new entries into the arkansas and mississippi soybean variety testing programs and entries submitted by extension nematologists from auburn university and louisiana state university. also included in the r. reniformis tests were the resistant cultivars forrest and hartwig, the susc ... | 2000 | 19271017 |
| replacement series: a tool for characterizing competition between phytoparasitic nematodes. | the replacement series approach was used to detect and define competition between meloidogyne incognita (mi) and rotylenchulus reniformis (rr) on soybean. in three greenhouse tests, soybean cv. davis seedlings were inoculated with 1,000 vermiform nematodes in the following mi:rr ratios: 0:0, 100:0, 75:25, 50:50, 25:75, and 0:100. after 86 days, relative nematode-yield values (number of each species in mixed culture divided by number in nonmixed culture) were calculated based on nematodes in soil ... | 1997 | 19274132 |
| extraction of root-associated meloidogyne incognita and rotylenchulus reniformis. | a technique based on physical maceration of root tissue was developed to extract vermiform and swollen stages of meloidogyne incognita and rotylenchulus reniformis. experiments conducted on soybean and tomato evaluated the efficiency of method (stir, grind), naoc1 concentration (0%, 0.5%), and duration (lx, 2x) on extraction of nematodes and eggs from 60-day-old populations. root-associated populations of r. reniformis were considerably lower than those of m. incognita, so development of the met ... | 1997 | 19274151 |
| tolerance to rotylenchulus reniformis and resistance to meloidogyne incognita race 3 in high-yielding breeding lines of upland cotton. | field experiments in 1992 and 1994 were conducted to determine the effect of rotylenchulus reniformis, reniform nematode, on lint yield and fiber quality of 10 experimental breeding lines of cotton (gossypium hirsutum) in untreated plots or plots fumigated with 1,3-dichloropropene. controls were la. rn 1032, a germplasm line possessing some resistance to r. reniformis, and stoneville 453, a cultivar that is susceptible to reniform nematode. several breeding lines produced greater lint yields tha ... | 1997 | 19274165 |
| relationship between meloidogyne incognita and rotylenchulus reniformis as influenced by soybean genotype. | the effect of soybean genotype on competition between meloidogyne incognita race 2 (mi) and rotylenchulus reniformis (rr) was evaluated in greenhouse and microplot replacement series experiments. soil in pots containing seedlings of 'davis' (susceptible to mi) or 'buckshot 66' (resistant to mi) was infested with 1,000 vermiform individuals in the following mi:rr ratios: 0:0, 100:0, 75:25, 50:50, 25:75, or 0:100. after 91 days, the relative nematode yields (number of nematodes in mixed culture di ... | 1997 | 19274173 |
| resistance to root-knot, reniform, and soybean cyst nematodes in selected soybean breeding lines. | soybean breeding lines and reported sources of nematode resistance were evaluated in repeated greenhouse tests for resistance to north carolina populations of the soybean cyst nematode heterodera glycines, reniform nematode rotylenchulus reniformis, and the root-knot nematode species meloidogyne incognita, m. arenaria, and m. arenaria. lines from the soybean breeding program in missouri that had 'hartwig' soybean as a parent were the most resistant to races 1-4 of the soybean cyst nematode and t ... | 1998 | 19274243 |
| resistance to meloidogyne incognita race 3 and rotylenchulus reniformis in wild accessions of gossypium hirsutum and g. barbadense from mexico. | forty-six accessions of g. hirsutum and two of g. barbadense were examined for resistance to meloidogyne incognita race 3 and rotylenchulus reniformis in environmental growth chamber experiments, with the objective of finding new sources of resistance. only the g. barbadense accessions, tx-1347 and tx-1348, supported significantly less reproduction by r. reniformis than the susceptible control, deltapine 16 (usda accession sa-1186). however, they were highly susceptible to m. incognita race 3. t ... | 1997 | 19274280 |
| regulation of population densities of heterodera cajani and other plant-parasitic nematodes by crop rotations on vertisols, in semi-arid tropical production systems in india. | the significance of double crop (intercrop and sequential crop), single crop (rainy season crop fallow from june to september), and rotations on densities of heterodera cajani, helicotylenchus retusus, and rotylenchulus reniformis was studied on vertisol (typic pellusterts) between 1987 and 1993. cowpea (vigna sinensis), mungbean (phaseolus aureus), and pigeonpea (cajanus cajan) greatly increased the population densities of h. cajani and suppressed the population densities of other plant-parasit ... | 1996 | 19277141 |
| impact of soil texture on the reproductive and damage potentials of rotylenchulus reniformis and meloidogyne incognita on cotton. | the effects of soil type and initial inoculum density (pi) on the reproductive and damage potentials of meloidogyne incognita and rotylenchulus reniformis on cotton were evaluated in microplot experiments from 1991 to 1993. the equilibrium nematode population density for r. reniformis on cotton was much greater than that of m. incognita, indicating that cotton is a better host for r. reniformis than m. incognita. reproduction of m. incognita was greater in coarse-textured soils than in fine-text ... | 1996 | 19277171 |
| changes in plant-parasitic nematode populations in pineapple fields following inter-cycle cover crops. | the use of plant-covers oat (arena sativa l.), rhodesgrass (chloris gayana kunth), soybean (glycine max [l.] merr.), and marigold (tagetes patula l.) during pineapple inter-cycle planting periods was investigated at two sites (kunia and whitmore, oahu, hi) as a potential means to reduce population densities of rotylenchulus reniformis, helicotylenchus dihystera, and paratylenchus spp. clean fallow and fallow covered with pineapple-plant residues (mulch) were the controls without plant-cover. reg ... | 1996 | 19277173 |
| greenhouse evaluation of selected soybean germplasm for resistance to north carolina populations of heterodera glycines, rotylenchulus reniformis, and meloidogyne species. | selected soybean genotypes were evaluated for resistance to north carolina populations of the soybean cyst nematode heterodera glycines, the root-knot nematodes meloidogyne incognita races 3 and 4, m. arenaria races 1 and 2, m. javanica, and the reniform nematode rotylenchulus reniformis in two greenhouse tests. populations of cyst nematode used in the first test were cultures from field samples originally classified as races 1-5, and those used in the second test included inbred cyst lines that ... | 1996 | 19277179 |
| resistance to the reniform nematode in selected soybean cultivars and germplasm lines. | reproduction indices from multiple tests were conducted to show the suitability of several soybean cultivars and germplasm lines as hosts of the reniform nematode rotylenchulus reniformis. sixteen soybean germplasm lines of 45 reported as resistant to soybean cyst nematode were also resistant to reinform nematode. cultivars peking and pickett, and pi 90763, used as differentials in the standardized soybean cyst nematode race determination test, were resistant to reniform nematode. the differenti ... | 1996 | 19277183 |
| 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 |
| occurrence of pasteuria-like organisms on selected plant-pamsitic nematodes of pineapple in the hawaiian islands. | soils from 320 sites representing diverse undisturbed habitats from five hawaiian islands were assessed for occurrence of pasteuria-like organisms. mean annual rainfall at sites ranged from 125-350 cm, elevation from 69-2,286 m, and annual mean temperature from 12-24 c. seven different natural communities were represented: wet lowland, mesic lowland, wet montane, mesk montane, dry montane, mesic subalpine, and dry alpine. pasteuria spp. in a soil sample was detected by baiting with infective sta ... | 1995 | 19277305 |
| evaluation of ethoprop and tetrathiocarbonate for reniform nematode control in pineapple. | ethoprop and disodium tetrathiocarbonate (ttc) were evaluated as replacements of fenamiphos and 1,3-dichloropropene (1,3-d) for control of rotylenchulus reniformis on pineapple in hawaii. treatments were established in a field on the del monte fresh fruit (hawaii) plantation in spring 1991. preplant soil treatments consisted of fumigation with 1,3-d at 226 kg a.i./ha and ttc at 135 kg or 270 kg a.i./ha. postplant nematicides for the 1,3-d treated plots were fenamiphos (3.4 kg a.i./ha trimonthly) ... | 1995 | 19277334 |
| comparison of single- and double-chisel injection methods for the control of rotylenchulus reniformis in pineapple. | the efficacy of 1,3-dichloropropene (1,3-d) applied with one or two chisels was determined for control of rotylenchulus reniformis on pineapple. the soil was fumigated with 1,3-d at 157 liters/ha with either a single chisel 46 cm deep or two chisels 41 cm deep in replicated experiments conducted in four commercial fields. soil samples were collected before fumigation and 45 days afterward from three depths and three positions. the three depths were 0-15, 16-30, and 31-45 cm; and the three positi ... | 1993 | 19279838 |
| comparison of two inoculum preparation methods for rotylenchulus reniformis. | three greenhouse experiments were conducted to determine whether naocl-extracted eggs would provide an acceptable inoculum source for rotylenchulus reniformis. two tests (one each on loamy sand and sandy clay) were designed to compare eggs extracted from roots with sodium hypochlorite (naocl) with mechanically extracted vermiform males, females, and juveniles from soil as inoculum sources. infection rates for both inoculum types were low (< 1-3%) on roots of 'ransom' soybean 14 days (loamy sand ... | 1993 | 19279839 |
| 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 |
| resistance to meloidogyne javanica and rotylenchulus reniformis in wild relatives of pigeonpea. | meloidogyne javanica and rotylenchulus reniformis are important nematode pests of pigeonpea. greenhouse evaluation of 66 accessions of 25 species of cajanus, rhynchosia, and flemingia for resistance to m. javanica based on number and size of galls, galled area of root, and number of egg masses showed resistance to be available in these wild relatives of pigeonpea. thirty-five accessions had </= 10 galls. five accessions of c. scarabaeoides (icpw 92, 101, 103, 128, and 133) had very small or no g ... | 1993 | 19279848 |
| reproductive and damage potentials of two populations of rotylenchulus reniformis on sweetpotato and related comparisons with meloidogyne javanica on tomato. | two rotylenchulus reniformis populations (north carolina and georgia) were compared on sweetpotato and tomato. 'beauregard' sweetpotato and 'better boy' and 'marion' tomato were excellent hosts for both r. reniformis populations. on beauregard sweetpotato, the two populations did not differ in fecundity; however, on both tomato cultivars, the georgia population reproduced at a higher rate than the north carolina population (p </= 0.05). meloidogyne javanica reproduction was higher (p </= 0.05) o ... | 1993 | 19279849 |
| plant-parasitic nematodes on soybean in south carolina. | fields in a concentrated area of soybean production in south carolina were chosen for soil sampling to determine the distribution of plant-parasitic nematodes. five hundred sampling sites were distributed over 19 counties according to county soybean acreage. helicotylenchus and scutellonema were identified most frequently from soil samples; together, these genera occurred in over 70% of the samples. pratylenchus and paratrichodorus were each observed in more than 60% of fields. meloidogyne spp. ... | 1993 | 19279859 |
| 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 |
| 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 |
| interrelationships of rotylenchulus reniformis with rhizoctonia solani on cotton. | the interrelationships between reniform nematode (rotylenchulus reniformis) and the cotton (gossypium hirsutum) seedling blight fungus (rhizoctonia solani) were studied using three isolates of r. solani, two populations of r. reniformis at multiple inoculum levels, and the cotton cultivars dehapine 90 (dp 90) and dehapine 41 (dp 41). colonization of cotton hypocotyl tissue by r. solani resulted in increases (p </= 0.05) in nematode population densities in soil and in eggs recovered from the root ... | 1994 | 19279918 |
| influence of rhizoctonia solani on egg hatching and infectivity of rotylenchulus reniformis. | the effects of culture filtrates of rhizoctonia solani and root exudates of r. solani-infected cotton (gossypium hirsutum) seedlings on hatching of eggs and infectivity of females of rotylenchulus reniformis were evaluated in an attempt to account for the enhanced nematode reproduction observed in the presence of this fungus. crude filtrates of r. solani cultures growing over sterile, deionized distilled water did not affect egg hatching. exudates from roots of cotton seedlings increased hatchin ... | 1994 | 19279919 |
| efficacy of paecilomyces lilacinus in suppressing rotylenchulus reniformis on tomato. | effects of rice-cultured paecilomyces lilacinus on rotylenchulus reniformis were studied in both greenhouse and field microplot tests with 'rutgers' tomato. numbers of r. reniformis were reduced (p </= 0.05) by p. lilacinus, with suppression in the initial greenhouse test ranging from 46 to 48% for two rice + p. lilacinus treatments; the rice-only treatment caused a nonsignificant reduction of 25%. in the second greenhouse test, total r. reniformis numbers were restricted (p </= 0.05) by 41% by ... | 1994 | 19279933 |
| reniform nematode reproduction and soybean yield of four soybean cultivars in arkansas. | a field infested with rotylenchulus reniformis in the arkansas river valley near pine bluff, jefferson county, arkansas, was used to test the effects of r. reniformis on four commonly grown soybean cultivars (lloyd, tracy-m, bedford, forrest). at planting, the plots averaged 950 vermiform reniform nematodes per 100 cm(3) of soil. at harvest, the average r. reniformis reproductive index (final/initial population density) was 2.62 for tracy-m, 2.50 for lloyd, 1.72 for bedford, and 0.81 for forrest ... | 1994 | 19279943 |
| reproduction of the reniform nematode on thirty soybean cultivars. | in greenhouse experiments conducted in 1991 and 1992, the 30 soybean (glycine max) cultivars most commonly grown in arkansas in 1990 were tested for resistance to the reniform nematode, rotylenchulus reniformis. 'forrest' was the most resistant cultivar, whereas 'braxton' was the most susceptible to r. reniformis. cultivars coker 485, centennial, stonewall, and sharkey did not differ from forrest (p = 0.01). cultivars lee 74, coker 6955, waiters, davis, pioneer 9442, and narow did not differ fro ... | 1994 | 19279944 |
| 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 |
| plant-parasitic nematodes associated with cotton in florida. | a sampling of 15% of the cotton hectarage in each florida county was assayed for nematodes and soil particle components following the 1990 harvest. the distribution of juveniles of meloidogyne spp., which were found in 61% of the 178 fields sampled statewide, was not influenced by soil type. rotylenchulus reniformis was more prevalent in the heavier soils and occurred in 15% of the sampled fields. in fields with concomitant infestations (9% of the sampled fields), densities of root-knot juvenile ... | 1994 | 19279958 |
| nematicide efficacy, root growth, and fruit yield in drip-irrigated pineapple parasitized by rotylenchulus reniformis. | a 3-year field trial near kunia, oahu, hawaii, was conducted to evaluate four nematicide treatments for efficacy against rotylenchulus reniformis in drip-irrigated pineapple (ananas comosus l. (merr.)). the treatments were (a) preplant fumigation with 1,3-dichloropropene (1,3-d) (336 liter/ ha) and postplant drip application of fenamiphos (3.4 kg/ha) with restricted irrigation, (b) preplant 1,3-d only, weekly irrigation, (c) 1,3-d fenamiphos, weekly irrigation, and (d) postplant fenamiphos only, ... | 1992 | 19283033 |
| host status of commercial maize hybrids to rotylenchulus reniformis. | the host status of 50 commercial maize hybrids for a mississippi population of rotylenchulus reniformis was determined in greenhouse experiments. reproduction was measured by determining rf values ([final egg number + juveniles and vermiform adults in soil] / initial egg number) and number of eggs per gram of fresh root. all hybrids maintained r. reniformis below the initial population level, indicating that they are relatively poor hosts for this species. rf values for r. reniformis among hybri ... | 1992 | 19283056 |
| 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 |
| carbon dioxide and temperature gradielits in baermann funnel extraction of rotylenchulus reniformis. | vermiform rotylenchulus reniformis were anesthetized in water by 10-40% co but were fully motile for 24 hours in water below 5% co. when air containing 2.5% co was blown onto agar, nematodes accumulated at the point of highest co concentration. nematodes also accumulated when chilling (0.2-1 c) of agar by the gas flow at the accumulation point was offset with heat from a fiber optic. in baermann funnels containing r. reniformis in silt loam and sandy clay loam soils, co in funnel water increased ... | 1991 | 19283091 |
| influence of nonhost plants on population decline of rotylenchulus reniformis. | the influence of chloris gayana, crotalaria juncea, digitaria decumbens, tagetes patula, and a chitin-based soil amendment on hawaiian populations of rotylenchulus reniformis was examined. chloris gayana was a nonhost for r. reniformis. the nematode did not penetrate the roots, and in greenhouse and field experiments, c. gayana reduced reniform nematode numbers at least as well as fallow. tagetes patula was a poor host for reniform nematode and reduced reniform nematode numbers in soil better th ... | 1991 | 19283098 |
| sterile culture of rotylenchulus reniformis on tomato root with gellan gum as a supporting medium. | rotylenchulus reniformis was repeatedly propagated in sterile excised tomato roots growing on modified white's medium with gellan gum as the support. gellan gum provided an optically clear support medium that could be liquified by adding 5 mm disodium ethylenediaminetetraacetate (edta) to facilitate nematode extraction. liquefaction of the gellan-gum medium by edta allowed efficient recovery of eggs and vermiform stages of r. reniformis. extraction efficiency was quantified with radopholus simil ... | 1991 | 19283117 |
| a collagenolytic fungus, cunninghamella elegans, for biological control of plant-parasitic nematodes. | the root-galling index of tomatoes inoculated with meloidogyne javanica was decreased 70% when collagen was used as a soil amendment (0.1% w/w) and 90% when the amendment was supplemented with the collagenolytic fungus cunninghamella elegans. the root-galling index was reduced 80% when the fungus was homogenized in collagen culture medium and added to soil without collagen supplement. culture filtrates of the fungus c. elegans, grown on collagen as a single source of carbon and nitrogen, immobil ... | 1991 | 19283126 |
| rotylenchulus reniformis on greenhouse-grown foliage plants: host range and sources of inoculum. | two sources of inoculum of reniform nematodes, rotylenchulus reniformis, were identified for infestation of ornamental foliage plants in commercial greenhouses. these were water from a local canal system and rooted cuttings purchased from other sources. eight ornamental plant species were identified as good hosts for the reniform nematode, with each species supporting a reniform population density equal to or greater than that supported by 'rutgers' tomato and a reproduction factor of greater th ... | 1991 | 19283176 |
| effects of nematicides and cuitivars on rotylenchulus reniformis and flue-cured tobacco yield. | main plots of tobacco cultivars were split into subplots treated or not treated with 1,3-d + chloropicrin. some differences (p = 0.05) occurred for tobacco yield, value, and r. reniformis populations among the 12 cultivars tested. treatment increased yields an average of 8.5%, but a significant cultivar x fumigation interaction did not occur. in a nematicide test, six of nine non-fumigant and fumigant nematicides significantly increased the value of tobacco cv. coker 371-gold by an average of $1 ... | 1991 | 19283190 |
| pineapple nematode research in hawaii: past, present, and future. | the first written record of pineapple in hawaii is from 1813. in 1901 commercial pineapple production started, and in 1924 the experiment station for pineapple research was established. nematode-related problems were recognized in the early 1900s by n. a. cobb. from 1920 to approximately 1945 nematode management in hawaiian pineapple was based on fallowing and crop rotation. during the 1920s and 1930s g. h. godfrey conducted research on pineapple nematode management. in the 1930s and 1940s m. b. ... | 1989 | 19287592 |
| accelerated movement of nematodes from soil in baermann funnels with temperature gradients. | baermann funnels were modified to eliminate or reverse the small temperature gradient (1-2 c/cm) across the soil layer that normally results from water evaporation. effects of modifications on extraction efficiency were examined at various ambient temperatures and after overnight adaptation of three nematode species at 20 and 30 c. extraction of meloidogyne incognita from sandy loam, tylenchulus semipenetrans from sandy clay loam, and rotylenchulus reniformis from silt was greatly accelerated si ... | 1989 | 19287622 |
| phytoparasitic nematode surveys of arkansas cotton fields, 1986-1988. | surveys from 1986 to 1988 identified 22 phytoparasitic nematode species in arkansas cotton fields. meloidogyne spp. was found in ca. 15% of the fields sampled. of these samples ca. 33% were found to have a population density of 106/100 cm(3) of soil or more. rotylenchulus reniformis was found in high numbers (5,000 +/100 cm(3) of soil) in 1% of the fields sampled in 1988. heterodera glycines was found in ca. 22% of the samples, presumably because of past cropping to soybean. other common species ... | 1989 | 19287659 |
| effects of soil solarization on nematodes parasitic to chickpea and pigeonpea. | solarization by covering the soil with transparent polyethylene sheets during the summer months (april, may, june) in 1984 and 1985 significantly (p = 0.01) reduced the population densities of nematodes (heterodera cajani, rotylenchulus reniformis, helicotylenchus retusus, pratylenchus sp., and tylenchorhynchus sp.) parasitic to chickpea and pigeonpea. population density reductions of 93% of heterodera cajani eggs and juveniles, 99% ofhelicotylenchus retusus, 98% of pratylenchus sp., and 100% of ... | 1990 | 19287776 |
| survey of current distribution of rotylenchulus reniformis in the united states. | the reniform nematode, rotylenchulus reniformis, has been reported from all gulf coast states, arkansas, hawaii, north carolina, and south carolina. experts in 11 states identified the counties or parishes where the nematode is found and provided information regarding associated soil parameters, climate, crops, and crop management. rotylenchulus reniformis has been detected in 187 counties and parishes of the southeastern united states and is most widespread in louisiana, mississippi, alabama, f ... | 1990 | 19287782 |
| response of rotylenchulus reniformis to nematicide applications on cotton. | field experiments were conducted to evaluate the efficacy of five nematicides for the management of rotylenchulus reniformis and for their effects on growth, development, and yield of cotton. treatments included 1,3-dichloropropene (1,3-d), fenamiphos, phorate, terbufos, aldicarb, and 1,3-d + aldicarb. average r. reniformis population densities across all treatments increased from 5,284 at 10 days after planting to a final density at harvest of 15,622 nematodes/500 cm(3) soil. the 1,3-d + aldica ... | 1990 | 19287784 |
| correlations of rotylenchulus reniformis population densities with 1,3-dichloropropene dosage rate and pineapple yields. | the relationships between rotylenchulus reniformis population densities and pineapple growth and yield were studied in a small-plot field experiment. increasing rates of handgun-injected 1,3-dichloropropene (1,3-d) preplant fumigant from 0 to 337 liters/ha resulted in greater nematode control, faster plant growth, and larger pineapple fruits. rotylenchulus reniformis population densities at 2, 4, 6, and 8 months postplant were correlated with plant size and yield. the shorter the time period fol ... | 1990 | 19287789 |
| effects of soil solarization on rotylenchulus reniformis in the lower rio grande valley of texas. | soil solarization was evaluated for control of rotylenchulus reniformis in the lower rio grande valley of texas. in field experiments, solarization significantly reduced soil nematode population densities 0-15 cm deep and increased yields of lettuce and cowpea. the length of time required for 90% mortality of nematodes in soil heated under controlled conditions in the laboratory varied from 25 hours to less than 1 hour between 41 and 47 c. daily exposures of nematode-infested soil to lethal temp ... | 1987 | 19290112 |
| plant-parasitic nematode problems in the pacific islands. | the pacific islands have a diverse range of food and cash crops with indigenous and introduced nematode problems. the staple food crops have serious nematode pests, such as meloidogyne spp. on sweet potato, hirschmanniella miticausa causing corm rot of taro, and pratylenchus coffeae and radopholus sp. producing tuber dry rot of yams. bananas are infested with p. coffeae or r. similis, citrus with tylenchulus semipenetrans, rice with aphelenchoides besseyi, and ginger with meloidogyne spp. and r. ... | 1988 | 19290200 |
| nematode problems affecting agriculture in the philippines. | nematodes are considered major pests on most economic crops in the philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. radopholus similis is the most destructive nematode on banana, while meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. tylenchulus semipenetrans is a problem on citrus and rotylenchulus reniformis on pineapple and some legume crops. hirschmanniella oryzae and aphelench ... | 1988 | 19290204 |
| effect of temperature on infection and survival of rotylenchulus reniformis. | from infestation of lettuce with preinfective females to egg deposition, populations of rotylenchulus reniformis from baton rouge, louisiana; lubbock and weslaco, texas; and mayaguez, puerto rico, required 41, 13, 7, and 7 days at 15, 20, 25, and 34 c, respectively. no nematode infection occurred at 10 c with any r. reniformis population, and the population from puerto rico did not reproduce at 15 c. nematode survival was not influenced by temperature, since populations from texas and louisiana ... | 1988 | 19290223 |
| geographical distributions of rotylenchulus reniformis, meloidogyne incognita, and tylenchulus semipenetrans in the lower rio grande valley as related to soil texture and land use. | a survey was conducted over a 22-year period to evaluate the influence of soil texture and land use on the geographical distributions of rotylenchulus reniformis, meloidogyne incognita, and tylenchulus semipenetrans in the lower rio grande valley. the distributions of r. reniformis and m. incognita were related to soil texture, whereas t. semipenetrans occurred wherever host plants were present regardless of soil texture. the incidence of m. incognita was greatest in elevated sandy loams and mod ... | 1987 | 19290268 |
| effect and reproduction of rotylenchulus reniformis on sweet potato selections. | growth, yield, and quality of 10 sweet potato selections and reproduction of the reniform nematode, rotylenchulus reniformis, were studied in fumigated and nonfumigated plots in a naturally infested field. nematode reproduction on the different selections in the field was similar to that reported in the greenhouse but was not related to the effect of the nematode on yield of the different selections. goldrush supported the least reproduction but was the most severely affected by the nematode, wh ... | 1983 | 19295791 |
| population dynamics of meloidogyne incognita and rotylenchulus reniformis alone and in combination, and their effects on sweet potato. | meloidogyne incognita (mi) and rotylenchulus reniformis (rr) interactions on sweet potato were studied in naturally and artificially infested field plots for 3 years. in a naturally infested field, early season counts of mi or rr were positively correlated with later counts of the same nematode, but negative correlations were found between early mi and subsequent rr, and early rr and subsequent mi counts. in field plots fumigated with methyl bromide and then infested with low levels of rr, mi, a ... | 1983 | 19295792 |
| parasitism of rotylenchulus reniformis on soybean root rhizobium nodules in venezuela. | | 1983 | 19295793 |
| effects of concomitant development on reproduction of meloidogyne incognita and rotylenchulus reniformis on sweet potato. | the influence of various factors on reproduction of concomitant meloidogyne incognita (mi) and rotylenchulus reniformis (rr) on sweet potato were studied in the greenhouse. reproduction of rr was reduced by mi at all inoculum levels and experiment durations used, while mi reproduction was not inhibited. both species failed to affect each other when inoculated simultaneously onto root systems developed in separate pots from different nodes of the same plant. reproduction of each species was not s ... | 1983 | 19295794 |
| resistant germplasm in gossypium species and related plants to rotylenchulus reniformis. | gossypium hirsutum, g. herbaceum, g. arboreum, g. barbadense, wild gossypium spp., hibiscus spp, and other malvaceae were tested in the greenhouse to identify germplasm resistant to rotylenchulus reniformis (rr). host resistance was based on rr egg production per gram of root compared with known g. hirsutum susceptible 'deltapine 16' as check. g. longicalyx and sida rhombifolia were nonhosts. high levels of resistance were found in g. stocksii, g. somalense, and g. barbadense 'texas 110.' other ... | 1984 | 19295892 |
| screening soybeans for resistance to reniform nematode disease in the philippines. | sixty-five soybean varieties were tested in the field for resistance to rotylenchulus reniformis. criteria for resistance or susceptibility were root necrosis, nematode recovery from roots and soil, and egg production. nine varieties were resistant, 13 moderately resistant, 26 moderately susceptible, and 17 susceptible. linear correlations between resistance rating and each assessment parameter were highly significantly positive, suggesting that any of the parameters could be used to identify re ... | 1979 | 19300647 |
| interrelations between meloidogyne javanica, rotylenchulus reniformis, and rhizobium sp. on vigna sinensis. | the interactions of meloidogyne javanica, rotylenchulus reniformis, and rhizobium sp. on cowpea seedlings were investigated. upon simultaneous inoculation with the two nematode species, m. javanica invaded first but did not affect root invasion by r. reniformis. m. javanica populations increased less in competition with r. reniformis than when present alone. preinvasion by r. renilormis significantly suppressed the number of m. javanica in the roots. inoculation of m. javanica and/or r. reniform ... | 1980 | 19300672 |