| broad meloidogyne resistance in potato based on rna interference of effector gene 16d10. | root-knot nematodes (meloidogyne spp.) are a significant problem in potato (solanum tuberosum) production. there is no potato cultivar with meloidogyne resistance, even though resistance genes have been identified in wild potato species and were introgressed into breeding lines. the objectives of this study were to generate stable transgenic potato lines in a cv. russet burbank background that carry an rna interference (rnai) transgene capable of silencing the 16d10 meloidogyne effector gene, an ... | 2015 | 25861119 |
| differential gene expression in roots of nematode-resistant and -susceptible peanut (arachis hypogaea) cultivars in response to early stages of peanut root-knot nematode (meloidogyne arenaria) parasitization. | the peanut root-knot nematode (rkn, meloidogyne arenaria) can cause significant yield losses in cultivated peanut (arachis hypogaea). however, molecular events underlying successful rkn infection and host responses in peanut are sparsely understood. using suppression subtractive hybridization (ssh), cdna libraries, enriched with differentially expressed ests, were constructed from rkn-challenged root tissues in the pre-penetration and early infection stages from near-isogenic nematode-resistant ... | 2011 | 20863592 |
| evaluation of an antibiotic-producing strain of pseudomonas fluorescens for suppression of plant-parasitic nematodes. | the antibiotic 2,4-diacetylphloroglucinol (dapg), produced by some strains of pseudomonas spp., is involved in suppression of several fungal root pathogens as well as plant-parasitic nematodes. the primary objective of this study was to determine whether wood1r, a d-genotype strain of dapg-producing p. fluorescens, suppresses numbers of both sedentary and migratory plant-parasitic nematodes. an experiment was conducted in steam-heated soil and included two seed treatments (with wood1r and a cont ... | 2009 | 22736820 |
| using fame analysis to compare, differentiate, and identify multiple nematode species. | we have adapted the sherlock(®) microbial identification system for identification of plant parasitic nematodes based on their fatty acid profiles. fatty acid profiles of 12 separate plant parasitic nematode species have been determined using this system. additionally, separate profiles have been developed for rotylenchulus reniformis and meloidogyne incognita based on their host plant, four species and three races within the meloidogyne genus, and three life stages of heterodera glycines. stati ... | 2009 | 22736811 |
| relationship between crop losses and initial population densities of meloidogyne arenaria in winter-grown oriental melon in korea. | to determine the economic threshold level, oriental melon (cucumis melo l. cv. geumssaragi-euncheon) grafted on shintozoa (cucurbita maxima x cu. moschata) was planted in plots (2 x 3 m) under a plastic film in february with a range of initial population densities (pi) of meloidogyne arenaria. the relationships of early, late, and total yield to pi measured in september and january were adequately described by both linear regression and the seinhorst damage model. initial nematode densities in s ... | 2002 | 19265907 |
| evaluation of steam and soil solarization for meloidogyne arenaria control in florida floriculture crops. | steam and soil solarization were investigated for control of the root-knot nematode meloidogyne arenaria in 2 yr of field trials on a commercial flower farm in florida. the objective was to determine if preplant steam treatments in combination with solarization, or solarization alone effectively controlled nematodes compared to methyl bromide (mebr). trials were conducted in a field with naturally occurring populations of m. arenaria. treatments were solarization alone, steam treatment after sol ... | 2016 | 27765992 |
| resistance in selected corn hybrids to meloidogyne arenaria and m. incognita. | a total of 33 corn hybrids were evaluated in a series of greenhouse and field trials to determine if they differed in resistance to either meloidogyne incognita race 3 or m. arenaria race 1. reproduction of m. incognita race 3 and m. arenaria race 1 on the hybrids was also compared. reproduction of m. arenaria differed among corn hybrids after 58 to 65 days in greenhouse experiments; however, reproduction was similar among hybrids in the field experiment. no hybrids were consistently resistant t ... | 2000 | 19271019 |
| reproduction of meloidogyne incognita race 3 on flue-cured tobacco homozygous for rk1 and/or rk2 resistance genes. | most commercial tobacco cultivars possess the rk1 resistance gene to races 1 and 3 of meloidogyne incognita and race 1 of meloidogyne arenaria, which has caused a shift in population prevalence in virginia tobacco fields toward other species and races. a number of cultivars now also possess the rk2 gene for root-knot resistance. experiments were conducted in 2013 to 2014 to examine whether possessing both rk1 and rk2 increases resistance to a variant of m. incognita race 3 compared to either gen ... | 2016 | 27418700 |
| genetic mapping of resistance to meloidogyne arenaria in arachis stenosperma: a new source of nematode resistance for peanut. | root-knot nematodes (rkn; meloidogyne sp.) are a major threat to crops in tropical and subtropical regions worldwide. the use of resistant crop varieties is the preferred method of control because nematicides are expensive, and hazardous to humans and the environment. peanut (arachis hypogaea) is infected by four species of rkn, the most damaging being m. arenaria, and commercial cultivars rely on a single source of resistance. in this study, we genetically characterize rkn resistance of the wil ... | 2015 | 26656152 |
| reproduction of meloidogyne spp. on resistant peanut genotypes from three breeding programs. | three described species of root-knot nematode parasitize peanut (arachis hypogaea): meloidogyne arenaria race 1 (ma), m. hapla (mh), and m. javanica (mj). peanut cultivars with broad resistance to meloidogyne spp. will be useful regardless of the species present in the field. the objective of this study was to determine whether peanut genotypes with resistance to m. arenaria originating from three different breeding programs were also resistant to m. hapla and m. javanica. the experiment used a ... | 2003 | 19262773 |
| virulence and molecular diversity of parthenogenetic root-knot nematodes, meloidogyne spp. | root-knot nematodes (rkn) are sedentary endoparasites causing severe damage to a wide variety of crops, including tomato. among them, the parthenogenetic species meloidogyne arenaria, m. incognita and m. javanica are of particular economic importance. the genetic diversity and relationships of 17 populations belonging to these three major species, either avirulent or virulent against the tomato mi resistance gene, were investigated in order to determine whether (a)virulence of the nematodes coul ... | 2000 | 10692014 |
| nucleotide substitution patterning within the meloidogyne rdna d3 region and its evolutionary implications. | evolutionary relationships based on nucleotide variation within the d3 26s rdna region were examined among acollection of seven meloidogyne hapla isolates and seven isolates of m. arenaria, m. incognita, and m. javanica. using d3a and d3b primers, a 350-bp region was pcr amplified from genomic dna and double-stranded nucleotide sequence obtained. phylogenetic analyses using three independent clustering methods all provided support for a division between the automictic m. hapla and the apomictic ... | 2003 | 19262771 |
| mechanism of resistance to meloidogyne arenaria in the peanut cultivar coan. | resistance to meloidogyne arenaria in the peanut cultivar coan is inherited as a single, dominant gene. the mechanism of resistance to m. arenaria in coan was evaluated in three experiments. in the first experiment the number of second-stage juveniles (j2) of m. arenaria penetrating roots of the susceptible cultivar florunner was higher than the number of j2 penetrating roots of the resistant peanut cultivar coan (p < 0.05). in a second experiment it was determined that the root size and number ... | 2003 | 19265984 |
| comparison of methods for assessing resistance to meloidogyne arenaria in peanut. | use of resistant cultivars is a desirable approach to manage the peanut root-knot nematode (meloidogyne arenaria). to incorporate resistance into commercially acceptable cultivars requires reliable, efficient screening methods. to optimize the resistance screening protocol, a series of greenhouse tests were done using seven genotypes with three levels of resistance to m. arenaria. the three resistance levels could be separated based on gall indices as early as two weeks after inoculation (wai) u ... | 2007 | 19259486 |
| mitochondrial genome plasticity among species of the nematode genus meloidogyne (nematoda: tylenchina). | the mitochondrial (mt) genomes of the plant-parasitic root-knot nematodes meloidogyne arenaria, meloidogyne enterolobii and meloidogyne javanica were sequenced and compared with those of three other root-knot nematode species in order to explore the mt genome plasticity within meloidogyne. the mt genomes of m. arenaria, m. enterolobii and m. javanica are circular, with an estimated size of 18.8, 18.9 and 19.6 kb, respectively. compared to other nematodes these mt genomes are larger, due to the p ... | 2015 | 25655462 |
| effect of castor and velvetbean organic amendments on meloidogyne arenaria in greenhouse experiments. | effectiveness of castor (ricinus communis) and velvetbean (mucuna deeringiana) amendments was tested for suppression of the root-knot nematode (meloidogyne arenaria) and growth of okra (hibiscus esculentus) in three greenhouse experiments. regression analysis was used to relate nematode population data or plant growth responses to various rates (0, 1, 2, 4, or 8 g/560 cm(3) soil pot) of each amendment in separate experiments. in general, plant growth parameters responded positively to the amendm ... | 1998 | 19274257 |
| evaluation of cover crops with potential for use in anaerobic soil disinfestation (asd) for susceptibility to three species of meloidogyne. | several cover crops with potential for use in tropical and subtropical regions were assessed for susceptibility to three common species of root-knot nematode, meloidogyne arenaria, m. incognita, and m. javanica. crops were selected based on potential use as organic amendments in anaerobic soil disinfestation (asd) applications. nematode juvenile (j2) numbers in soil and roots, egg production, and host plant root galling were evaluated on arugula (eruca sativa, cv. nemat), cowpea (vigna unguicula ... | 2013 | 24379486 |
| rkn lethal db: a database for the identification of root knot nematode (meloidogyne spp.) candidate lethal genes. | root knot nematode (rkn; meloidogyne spp.) is one of the most devastating parasites that infect the roots of hundreds of plant species. rkn cannot live independently from their hosts and are the biggest contributors to the loss of the world's primary foods. rnai gene silencing studies have demonstrated that there are fewer galls and galls are smaller when rnai constructs targeted to silence certain rkn genes are expressed in plant roots. we conducted a comparative genomics analysis, comparing rk ... | 2012 | 23144556 |
| resistance of interspecific arachis breeding lines to meloidogyne javanica and an undescribed meloidogyne species. | resistance to a peanut-parasitic population of meloidogyne javanica and an undescribed meloidogyne sp. in peanut breeding lines selected for resistance to meloidogyne javanica was examined in greenhouse tests. the interspecific hybrid txag-7 was resistant to reproduction of meloidogyne javanica, m. javanica, and meloidogyne sp. an meloidogyne javanica-resistant selection from the second backcross (bc) of txag-7 to the susceptible cultivar florunner also was resistant to m. javanica but appeared ... | 1998 | 19274226 |
| virulence of meloidogyne spp. and induced resistance in grape rootstocks. | harmony grape rootstock displays resistance to several meloidogyne spp. but that resistance is not durable in commercial vineyard settings. a 2-year experiment in a microplot setting revealed host specificities of two virulent populations of meloidogyne arenaria and an avirulent population of meloidogyne incognita. in a subsequent split-root experiment, the avirulent nematode population was demonstrated to induce resistance to the virulent nematode population. to quantify the level of resistance ... | 2007 | 19259475 |
| the heat-stable root-knot nematode resistance gene mi-9 from lycopersicon peruvianum is localized on the short arm of chromosome 6. | the tomato gene mi-1 confers resistance to three species of root-knot nematodes, meloidogyne spp. however, the resistance mediated by mi-1 is inactive at soil temperatures above 28 degrees c. previously, we identified and mapped a novel heat-stable nematode resistance gene from the wild species lycopersicon peruvianum accession la2157 on to chromosome 6. here we report further characterization of this heat-stable resistance against three mi-1-avirulent biotypes of meloidogyne javanica, meloidogy ... | 2003 | 12589548 |
| potential of leguminous cover crops in management of a mixed population of root-knot nematodes (meloidogyne spp.). | root-knot nematode is an important pest in agricultural production worldwide. crop rotation is the only management strategy in some production systems, especially for resource poor farmers in developing countries. a series of experiments was conducted in the laboratory with several leguminous cover crops to investigate their potential for managing a mixture of root-knot nematodes (meloidogyne arenaria, m. incognita, m. javanica). the root-knot nematode mixture failed to multiply on mucuna prurie ... | 2010 | 22736854 |
| sensitive pcr detection of meloidogyne arenaria, m. incognita, and m. javanica extracted from soil. | we have developed a simple pcr assay protocol for detection of the root-knot nematode (rkn) species meloidogyne arenaria, m. incognita, and m. javanica extracted from soil. nematodes are extracted from soil using baermann funnels and centrifugal flotation. the nematode-containing fraction is then digested with proteinase k, and a pcr assay is carried out with primers specific for this group of rkn and with universal primers spanning the its of rrna genes. the presence of rkn j2 can be detected a ... | 2006 | 19259460 |
| preliminary study of the green algae chlorella (chlorella vulgaris) for control on the root-knot nematode (meloidogyne arenaria) in tomato plants and ectoparasite xiphinema indexin grape seedlings. | the alternative ecological methods require investigation of many organo-biological means for plant protection against dangerous root parasites such as root-knot nematode meloidogyne arenaria and some ectoparasites (xiphinema index). the bulgarian organic product - dry extract of green alga chlorella vulgaris ("the golden apple"-plamen barakov) is the latest product, which in comparative aspect gives the best results. series of laboratory and pot experiments are carried out with tomato (cv. bele ... | 2005 | 16628939 |
| penetration and development of meloidogyne arenaria on two new grape rootstocks. | penetration, development, and reproduction of a virulent 'harmony' population of meloidogyne arenaria was studied on two nematode-resistant grape rootstocks 10-17a and 6-19b. 'cabernet sauvignon' was used as a susceptible control for comparison. plants were inoculated with 100 freshly hatched second-stage juveniles (j2) of m. arenaria. greater numbers of j2 penetrated roots of 'cabernet' than 10-17a, and none penetrated roots of 6-19b 4 days after inoculation (dai). at 7 dai, vermiform j2 advanc ... | 2002 | 19265923 |
| conserved and variable domains in satellite dnas of mitotic parthenogenetic root-knot nematode species. | two satellite dnas have been characterized in the mitotic parthenogenetic root-knot nematodes meloidogyne javanica and m. paranaensis, agriculturally important phytoparasitic species. the satellite repeat variants cloned from m. javanica could not be resolved from those described earlier in m. arenaria [castagnone-sereno, p., leroy, f., abad, p., 2000. cloning and characterization of an extremely conserved satellite dna family from the root-knot nematode meloidogyne arenaria. genome 43, 346-353] ... | 2005 | 16229973 |
| a recessive gene for resistance to meloidogyne arenaria in interspecific arachis spp. hybrids. | a single dominant gene for resistance to meloidogyne arenaria was identified previously in two peanut cultivars, arachis hypogaea 'coan' and 'nematam'. the interspecific arachis hybrid txag-6 was the source of this resistance and the donor parent in a backcross breeding program to introgress resistance into cultivated peanut. to determine if other resistance genes were present in txag-6 and derived breeding populations from the third backcross generation (bc), f individuals were evaluated for th ... | 2005 | 19262858 |
| coprinus comatus: a basidiomycete fungus forms novel spiny structures and infects nematode. | nematophagous basidiomycete fungi kill nematodes by trapping, endoparasitizing and producing toxin. in our studies coprinus comatus (o.f.müll. : fr.) pers. is found to be a nematode-destroying fungus; this fungus immobilizes, kills and uses free-living nematode panagrellus redivivus goodey and root-knot nematode meloidogyne arenaria neal. c. comatus produces an unusual structure designated spiny ball. set on a sporophore-like branch, the spiny ball is a burr-like structure assembled with a large ... | 2010 | 21148944 |
| evaluation of changes in the element content and biomass of invaded with meloidogyne arenaria tiny tim tomato plants under nh4vo3 treatment. | the parasite-host system meloidogyne arenaria--tiny tim tomato plants has been studied in order to investigate the influence of the process of invasion on the chemical composition and biomass of plants. the concentrations of seven chemical elements cu, zn, mg, k, na, mn and fe have been determined using aas in controls and invaded plants, and their changes have been evaluated under treatment with nh4vo3 in three different concentrations 0.01, 0.1 and 0.13 mg/100 ml h2o. the process of treatment ... | 2003 | 14711041 |
| developmental response of a resistance-breaking population of meloidogyne arenaria on vitis spp. | pre- and post-infection resistance mechanisms expressed by vitis rootstocks rs-9 and teleki 5c against second-stage juveniles (j2) of resistance-breaking populations of meloidogyne arenaria were observed and correlated with juvenile development and nematode reproduction. cabernet sauvignon grape was used as a susceptible control for comparison. similar numbers of j2 penetrated teleki 5c and cabernet sauvignon roots. root-tip necrosis, a hypersensitive reaction, occurred in both rootstocks but wa ... | 2002 | 19265904 |
| host status of endophyte-infected and noninfected tall fescue grass to meloidogyne spp. | tall fescue grass cultivars with or without endophytes were evaluated for their susceptibility to meloidogyne incognita in the greenhouse. tall fescue cultivars evaluated included, i) wild-type jesup (e+, ergot-producing endophyte present), ii) endophyte-free jesup (e-, no endophyte present), iii) jesup (max-q, non-ergot producing endophyte) and iv) georgia 5 (e+). peach was included as the control. peach supported greater (p ≤ 0.05) reproduction of m. incognita than all tall fescue cultivars. d ... | 2010 | 22736851 |
| meloidogyne javanica on peanut in florida. | a mixed population of meloidogyne arenaria race 1 and m. javanica race 3 is reported on peanut from a field in levy county, florida. confirmation of m. javanica on peanut is based on esterase and malate dehydrogenase isozyme patterns resolved on polyacrylamide slab gels following electrophoresis, and perineal patterns. up to 29% of 290 individual females collected from peanut roots in the field in autumn 2002 showed a typical esterase j3 phenotype for m. javanica. this is the third report of m. ... | 2003 | 19262776 |
| rate response of 1,3-dichloropropene for nematode control in spring squash in deep sand soils. | the soil fumigant 1,3-dichloropropene (1,3-d) formulated with chloropicrin is viewed as a likely alternative for replacing methyl bromide in florida when the latter is phased out in 2005. therefore, it behooves us to learn more about using 1,3-d in deep, sand soils. two trials were conducted on spring squash to determine the most effective rate of 1,3-d for the control of meloidogyne spp. rates tested included 0, 56, 84, 112, and 168 liters/ha of 1,3-d applied broadcast with conventional chisels ... | 2000 | 19271005 |
| 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 |
| reproductive variability of field populations of meloidogyne spp. on grape rootstocks. | variability in penetration, development, and reproduction of two resistance-breaking field pathotypes (pt.) of meloidogyne arenaria, m. incognita, and a population of mixed meloidogyne spp. virulent to grape hosts were compared on two resistant vitis rootstocks 'freedom' and 'harmony' in separate tests. 'cabernet sauvignon' was included as a susceptible host to all four nematode populations. secondstage juveniles (j2) of the mixed population failed to penetrate freedom roots. by contrast, 6% of ... | 2000 | 19270976 |
| population dynamics of meloidogyne arenaria and pasteuria penetrans in a long-term crop rotation study. | the endospore-forming bacterium pasteuria penetrans is an obligate parasite of root-knot nematodes (meloidogyne spp.). the primary objective of this study was to determine the effect of crop sequence on abundance of p. penetrans. the experiment was conducted from 2000 to 2008 at a field site naturally infested with both the bacterium and its host meloidogyne arenaria and included the following crop sequences: continuous peanut (arachis hypogaea) (p-p-p) and peanut rotated with either 2 years of ... | 2009 | 22736828 |
| molecular and morphological characterization of an unusual meloidogyne arenaria population from traveler's tree, ravenala madagascariensis. | an unusual variant of meloidogyne arenaria was discovered on roots of a traveler's tree (ravenala madagascariensis) intended for display at a public arboretum in pennsylvania. the population aroused curiosity by the lack of visible galling on the roots of the infected plant, and the female vulval region was typically surrounded by egg sacs. most morphometrics of the population fit within the ranges reported for m. arenaria, with a mosaic of features in common with either m. platani or other trop ... | 2008 | 19440257 |
| host suitability of potential cover crops for root-knot nematodes. | several potential cover crops were evaluated for their susceptibility to meloidogyne arenaria race 1, m. incognita race 1, and m. javanica in a series of five greenhouse experiments. no galls or egg masses were observed on roots of castor (ricinus communis), cowpea (vigna unguiculata cv. iron clay), crotalaria (crotalaria spectabilis), or american jointvetch (aeschynomene americana). occasional egg masses (rating </=1.0 on 0-5 scale) were observed on marigold (tagetes minuta) in one test with m. ... | 1999 | 19270926 |
| genetics and mechanism of resistance to meloidogyne arenaria in peanut germplasm. | segregation of resistance to meloidogyne arenaria in six bcf peanut breeding populations was examined in greenhouse tests. chi-square analysis indicated that segregation of resistance was consistent with resistance being conditioned by a single gene in three breeding populations (tp259-3, tp262-3, and tp271-2), whereas two resistance genes may be present in the breeding populations tp259-2, tp263-2, and tp268-3. nematode development in clonally propagated lines of resistant individuals of tp262- ... | 1999 | 19270898 |
| bahiagrass, corn, cotton rotations, and pesticides for managing nematodes, diseases, and insects on peanut. | florunner peanut was grown after 1 and 2 years of tifton 9 bahiagrass, corn, cotton, and continuous peanut as whole-plots. pesticide treatments aldicarb (3.4 kg a.i./ha), flutolanil (1.7 kg a.i./ha), aldicarb + flutolanil, and untreated (control) were sub-plots. numbers of meloidogyne arenaria second-stage juveniles in the soil and root-gall indices of peanut at harvest were consistently lower in plots treated with aldicarb and aldicarb + flutolanil than in flutolanil-treated and untreated plots ... | 1999 | 19270889 |
| management of plant-parasitic nematodes on peanut with selected nematicides in north carolina. | field experiments were conducted to determine peanut growth and yield responses to selected fumigant and nonfumigant nemaficide treatments in 1988 and 1989. all treatments with the fumigant 1, 3-d significantly suppressed nematode reproduction (meloidogyne arenaria, m. hapla, and mesocriconema ornatum) and enhanced peanut yields over the other treatments in four tests in 1988. yield increases with the fumigant ranged from about 20% to 100% over the untreated control. test sites in 1989 had lower ... | 1998 | 19274260 |
| effect of meloidogyne arenaria and mulch type on okra in microplot experiments. | the effects of perennial peanut (arachis glabrata) hay, an aged yard-waste compost (mainly woodchips), and a control treatment without amendment were determined on two population levels of root-knot (melaidogyne arenaria) nematode over three consecutive years in field microplots. okra (hibiscus esculentus, susceptible to the root-knot nematode) and a rye (secale cereale) cover crop (poor nematode host) were used in the summer and winter seasons, respectively. the organic amendment treatments aff ... | 1998 | 19274256 |
| morphological comparison of seven hypotriploid populations of meloidogyne arenaria with the typical triploid populations. | a morphological comparison of seven hypotriploid populations of meloidogyne arenaria was made to clarify their taxonomic status, using light and scanning electron microscopy. all populations differed from each other and from the typical triploid m. arenaria by certain features. differences were not regarded as sufficient to justify recognition of the variants as distinct species. morphological divergence of populations from the typical m. arenaria was gradual. the most useful characters were sty ... | 1993 | 19279750 |
| host status of herbaceous perennials to meloidogyne incognita and m. arenaria. | twenty-two different herbaceous perennials were studied for their reaction to separate inoculations of meloidogyne arenaria and m. incognita under greenhouse conditions. perennial taxa that did not develop root-galls following inoculation, and therefore are considered as nonhosts of both nematode species, included species and cultivars of aethionema, fragaria, phlox, and polygonum. echinacea, monarda, and patrinia developed only a few galls. root-galls developed on species and cultivars of achil ... | 1998 | 19274254 |
| high-resolution dna fingerprinting of parthenogenetic root-knot nematodes using aflp analysis. | amplified fragment length polymorphism (aflp) analysis has been used to characterize 15 root-knot nematode populations belonging to the three parthenogenetic species meloidogyne arenaria, m. incognita and m. javanica. sixteen primer combinations were used to generate aflp patterns, with a total number of amplified fragments ranging from 872 to 1087, depending on the population tested. two kinds of polymorphic dna fragments could be distinguished: bands amplified in a single genotype, and bands p ... | 1998 | 9465419 |
| field evaluation of susceptibility to meloidogyne arenaria in arachis hypogaea plant introductions. | resistance to meloidogyne arenaria race 1 is not currently available in commercial peanut cultivars. moderate levels of resistance have been identified in arachis hypogaea plant introductions (pi) in previous greenhouse studies. the purpose of this work was to evaluate the effects of resistance in peanut pi on populations dynamics of m. arenaria in field plots. the pi designated as resistant in greenhouse studies had fewer m. arenaria in roots than the most susceptible pi. at midseason and at th ... | 1992 | 19283050 |
| damage functions for three meloidogyne species on arachis hypogaea in texas. | the yield response of florunner peanut to different initial population (pi) densities of meloidogyne arenaria, m. javanica, and an undescribed meloidogyne species (isolate 93-13a) was determined in microplots in 1995 and 1996. seven pi's (0, 0.5, 1, 5, 10, 50, and 100 eggs and j2/500 cm(3) soil) were used for each meloidogyne species in both years. the three species reproduced abundantly on florunner in both years. in 1995, mean reproduction differed among the three species; mean rf values were ... | 1997 | 19274184 |
| effects of temperature on resistance in phaseolus vulgaris genotypes and on development of meloidogyne species. | phaseolus vulgaris lines with heat-stable resistance to meloidogyne spp. may be needed to manage root-knot nematodes in tropical regions. resistance expression before and during the process of nematode penetration and development in resistant genotypes were studied at pre- and postinoculation temperatures of 24 degrees c and 24 degrees c, 24 degrees c and 28 degrees c, 28 degrees c and 24 degrees c, and 28 degrees c and 28 degrees c. resistance was effective at all temperature regimes examined, ... | 1997 | 19274137 |
| comparison of sequences from the ribosomal dna intergenic region of meloidogyne mayaguensis and other major tropical root-knot nematodes. | the unusual arrangement of the 5s ribosomal gene within the intergenic sequence (igs) of the ribosomal cistron, previously reported for meloidogyne arenaria, was also found in the ribosomal dna of two other economically important species of tropical root-knot nematodes, m, incognita and m. javanica. this arrangement also was found in m. hapla, which is important in temperate regions, and m. mayaguensis, a virulent species of concern in west africa. amplification of the region between the 5s and ... | 1997 | 19274129 |
| responses of meloidogyne arenaria and m. incognita to green manures and supplemental urea in glasshouse culture. | the recent loss of many effective nematicides has led to renewed interest in alternative methods of nematode management. greenhouse experiments were conducted to determine the effects of rapeseed and velvetbean green manures, and supplemental urea, on the root-knot nematodes meloidogyne arenaria and m. incognita. green manures were incorporated with m. arenaria-infested soil using rates totaling 200,300, and 400 mg n/kg soil. squash plants grown in this soil were evaluated using a gall index and ... | 1996 | 19277190 |
| identification of rapd, scar, and rflp markers tightly linked to nematode resistance genes introgressed from arachis cardenasii into arachis hypogaea. | two dominant genes conditioning resistance to the root-knot nematode meloidogyne arenaria were identified in a segregating f2 population derived from the cross of 4x (arachis hypogaea x arachis cardenasii)-ga 6 and pi 261942. mae is proposed as the designation for the dominant gene restricting egg number and mag is proposed as the designation for the dominant gene restricting galling. the high levels of resistance in ga 6 were introgressed from a. cardenasii and, therefore, a search to identify ... | 1996 | 8890516 |
| host suitability and response of asparagus cultivars to meloidogyne species and races. | the host-parasite relationships of asparagus and meloidogyne spp. were examined under greenhouse and microplot conditions. meloidogyne species and races differed greatly in their ability to reproduce on asparagus seedlings. meloidogyne hapla generally failed to reproduce, and m. javanica, m. arenaria race 1, and m. incognita race 3 reproduced poorly, with a reproduction factor (rf = final population/initial population) usually < 1.0. only m. arenaria race 2 and m. incognita races 1 and 4 reprodu ... | 1992 | 19283211 |
| role of nematodes, nematicides, and crop rotation on the productivity and quality of potato, sweet potato, peanut, and grain sorghum. | the objective of this experiment was to determine the effects of fenamiphos 15g and short-cycle potato (po)-sweet potato (sp) grown continuously and in rotation with peanut (pe)-grain sorghum (gs) on yield, crop quality, and mixed nematode population densities of meloidogyne arenaria, m. hapla, m. incognita, and mesocriconema ornatum. greater root-gall indices and damage by m. hapla and m. incognita occurred on potato than other crops. most crop yields were higher and root-gall indices lower fro ... | 1996 | 19277157 |
| penetration and post-infectional development and reproduction of meloidogyne arenaria races 1 and 2 on susceptible and resistant soybean genotypes. | penetration, post-infectional development, reproduction, and fecundity of meloidogyne arenaria races 1 and 2 were studied on susceptible (cns), partially resistant (jackson), and highly resistant (pi 200538 and pi 230977) soybean genotypes in the greenhouse. the ability to locate and invade roots was similar between races, but more juveniles penetrated roots of susceptible cns than the resistant genotypes. at 10 days after inoculation, 56% and 99% to 100% of race 1 second-stage juveniles were ve ... | 1996 | 19277152 |
| characterization of acetylcholinesterase molecular forms of the root-knot nematode, meloidogyne. | multiple molecular forms of acetylcholinesterase have been isolated and characterized from the root-knot nematodes meloidogyne arenaria and meloidogyne incognita. the forms of enzyme present in these 2 species are similar but not identical to those that occur in the free-living nematode caenorhabditis elegans. the 5 enzyme forms exhibit differential solubilities and can be classified into 3 classes, a, b, and c, based on substrate affinity, inhibitor and detergent sensitivity, and thermal inacti ... | 1991 | 1775164 |
| cellular responses of resistant and susceptible soybean genotypes infected with meloidogyne arenaria races 1 and 2. | the cellular responses induced by meloidogyne arenaria races 1 and 2 in three soybean genotypes, susceptible cns, resistant jackson, and resistant pi 200538, were examined by light microscopy 20 days after inoculation. differences in giant-cell development were greater between races than among the soybean genotypes. m. arenaria race 1 stimulated small, poorly formed giant-cells in contrast with m. arenaria race 2, which induced well-developed, thick-walled, multinucleate giant-cells. the number ... | 1996 | 19277138 |
| surface coat of meloidogyne incognita. | the nematode surface coat is defined as an extracuticular component on the outermost layer of the nematode body wall, visualized only by electron microscopy. surface coat proteins of meloidogyne incognita race 3 infective juveniles were characterized by electrophoresis and western blotting of extracts from radioiodine and biotin-labeled nematodes. extraction of labeled nematodes with cetyltrimethylammonium bromide yielded a principal protein band larger than 250 kda and, with water soluble bioti ... | 1996 | 19277137 |
| race composition of meloidogyne incognita and m. arenaria populations in vegetable fields in uttar pradesh. | a total of 1,256 populations of meloidogyne incognita and 442 populations of m. arenaria were collected from vegetables in eight districts of uttar pradesh, india. host differentials were used to identify the host race of each population. all four host races of m. incognita were present in six of the eight districts. in the other two districts, only host races 1, 2, and 4 were found. although frequencies of occurrence of the races differed among districts, races 1 and 2 comprised 62% of all m. i ... | 1991 | 19283172 |
| inheritance of resistance to the root-knot nematode meloidogyne arenaria in myrobalan plum. | the inheritance of resistance of the self-incompatible myrobalan plum prunus cerasifera to the root-knot nematode meloidogyne arenaria was studied using first a diallel cross between five parents of variable host suitability (including two highly resistant clones p.1079 and p.2175, a moderate host p.2032, a good host p.2646 and an excellent host p.16.5), followed by the g2 crosses p.16.5 × (p.2646 × p.1079) and p.2646 × (p.16.5 × p.1079). a total of 355 g1 and 72 g2 clones obtained from hard-woo ... | 1996 | 24166553 |
| 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 |
| development of meloidogyne arenaria on peanut and soybean under two temperature cycles. | florunner peanut and three soybean cultivars, centennial, gasoy 17, and wright, were inoculated with 48-hour age cohorts of meloidogyne arenari race 1 second-stage juveniles and placed in a growth chamber set to simulate early season (low temperature) and midseason (high temperature) conditions. percentages of the initial inoculum penetrating roots 4 and 8 days after inoculation were 2-3 times higher in soybean cultivars than in peanut; 25% on susceptible soybean and 9% on peanut. penetration an ... | 1991 | 19283157 |
| effects of peanut genotypes on meloidogyne species interactions. | a 3-year microplot study was conducted to characterize the interaction between meloidogyne arenaria race 1 (ma1) and m. hapla (mh), as affected by the five peanut genotypes: florigiant, nc 7, nc 6, nc ac 18416, and nc ac 18016. the interactive effects on infection (total parasitic forms per root unit) and reproduction potentials of each nematode species and crop damage were determined. as a single population, ma1 had greater infection capacity and caused more crop damage than did mh, but both sp ... | 1995 | 19277279 |
| intra- and interpopulation genome variation in meloidogyne arenaria. | the genetic heterogeneity of two m. arenaria race 2 populations (designated pelion and govan) was examined using rflp analysis of 12 clonal lines established from single egg masses (six distinct clonal lines from each population). these populations are essentially identical by traditional biochemical and race identification schemes; however, the govan population is more aggressive than the pelion population, producing larger galls and exhibiting greater reproductive capabilities on many soybean ... | 1995 | 19277274 |
| repeats and subrepeats in the intergenic spacer of rdna from the nematode meloidogyne arenaria. | ribosomal dna (rdna) repeats of the plant-parasitic nematode meloidogyne arenaria are heterogeneous in size and appear to contain 5s rrna gene sequences. moreover, in a reca+ bacterial host, plasmid clones of a 9 kb rdna repeat show deletion events within a 2 kb intergenic spacer (igs), between 28s and 5s dna sequences. these deletions appear to result from a reduction in the number of tandem 129 bp repeats in the igs. the loss of such repeats might explain how rdna length heterogeneity, observe ... | 1991 | 2062313 |
| size differences among root-knot nematodes on resistant and susceptible alyceclover genotypes. | the influence of plant resistance on the size of individual root-knot nematodes was determined in greenhouse experiments. five genotypes of alyceclover were inoculated with second-stage juveniles of meloidogyne incognita race 3 or m. arenaria race 1. plants were harvested at selected intervals and stained for detection of the nematodes, which were dissected from the roots. length, width, and sagittal-sectional area of each animal were measured using an image-analysis system, and areas of nematod ... | 1991 | 19283120 |
| meloidogyne javanica parasitic on peanut. | peanut fields in four governorates of egypt were surveyed to identify species of meloidogyne present. fourteen populations obtained from peanut roots were all identified as m. javanica based on perineal patterns, stylet and body lengths of second-stage juveniles, esterase phenotypes, and restriction fragment length polymorphisms of mtdna. three of 14 populations, all from contiguous fields in the behara governorate, had individuals with a unique two-isozyme esterase phenotype. all populations of ... | 1994 | 19279913 |
| resistance of maize to meloidogyne arenaria and meloidogyne javanica. | a diallel cross of eight maize, zea mays l., inbred lines was analyzed for reaction to two species of root-knot nematodes, meloidogyne arenaria (neal) chitwood and m. javanica (treub) chitwood. egg production following inoculation of f1 hybrid seedlings with nematode eggs was determined in a greenhouse experiment. data were analyzed using griffing's method 4, model i. general combining ability was a significant source of variation in egg production of both m. arenaria and m. javanica; specific c ... | 1990 | 24221114 |
| evaluation of soybean cultivars for production in meloidogyne arenaria race 2-infested soil. | field trials with 56 soybean cultivars and breeding lines from public and private sources were conducted from 1986 through 1988 at a site infested with meloidogyne arenaria race 2. differences (p < 0.05) among yields were found each year and yields were negatively correlated (p < 0.01) with root-knot nematode galling. all entries were galled and the highest-yielding entries, 'kirby' and 'coker 6738', were determined to have average yield reductions of 56% and 62%, respectively, when compared wit ... | 1990 | 19287790 |
| resistance in lycopersicon peruvianum to isolates of mi gene-compatible meloidogyne populations. | root-knot nematode resistance of f progeny of an intraspecific hybrid (lycopersicon peruvianum var. glandulosum acc. no. 126443 x l. peruvianum acc. no. 270435), l. esculentum cv. piersol (possessing resistance gene mi), and l. esculentum cv. st. pierre (susceptible) was compared. resistance to 1) isolates of two meloidogyne incognita populations artificially selected for parasitism on tomato plants possessing the mi gene, 2) the wild type parent populations, 3) four naturally occurring resistan ... | 1990 | 19287762 |
| expression of resistance to meloidogyne arenaria in arachis batizocoi and a. cardenasii. | | 1990 | 19287741 |
| expression of resistance to meloidogyne arenaria in arachis batizocoi and a. cardenasii. | | 1990 | 19287717 |
| 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 |
| crops uncommon to alabama for the management of meloidogyne arenaria in peanut. | in a 1987 field study juveniles of meloidogyne arenaria assayed at the time of peanut harvest were almost undetectable in plots planted with american jointvetch (aeschynomene americana), castor bean (ricinus communis), partridge pea (cassia fasiculata), sesame (sesamum indicum), and cotton (gossypium hirsutum), whereas plots with peanut (arachis hypogaea) averaged 120 juveniles/100 cm(3) soil. application of aldicarb in peanut resulted in an average of 27 juveniles/100 cm(3) soil. in 1988 all pl ... | 1989 | 19287678 |
| effects of bahiagrass and nematicides on meloidogyne arenaria on peanut. | a field infested with meloidogyne arenaria and with a history of peanut yield losses was divided into two equal parts. one-half of the field (bahia site) was planted to bahiagrass in 1986 and maintained through 1987. the other half (peanut site) was planted to soybean in 1986 and peanut in 1987 with hairy vetch planted each fall as a cover crop. in 1988 identical nematicide treatments including 1,3-dichloropropene (1,3-d), aldicarb, and ethoprop were applied to the two sites, and the sites were ... | 1989 | 19287670 |
| cloning and characterization of an extremely conserved satellite dna family from the root-knot nematode meloidogyne arenaria. | a new satellite dna family, named pmae, has been cloned from the genome of the phytoparasitic nematode, meloidogyne arenaria (nematoda: tylenchida). it is represented as tandemly repeated sequences with a monomeric unit of 172 bp. the monomers are present at approximately 15700 copies per haploid genome, and represent about 5.3% of the total genomic dna. twenty-seven independent monomers have been cloned and sequenced. the deduced consensus sequence is 70.9% a + t rich, with frequent stretches o ... | 2000 | 10791824 |
| low, but strongly structured mitochondrial dna diversity in root knot nematodes (meloidogyne). | root-knot nematodes (genus meloidogyne) have been the subject of recent and numerous studies of genetic variation because of the need to develop molecular diagnostics for the four globally distributed, parthenogenetic species that are significant agricultural pests. our analysis of meloidogyne mtdna improves on previous studies: (i) by examining restriction site polymorphism among a large number of isolates also characterized for standard morphological, host range and allozyme phenotypes; (ii) b ... | 1994 | 7911772 |
| suitability of small grains as hosts of meloidogyne species. | seven cultivars of wheat, five of oat, one of rye, and four of barley were tested as hosts for meloidogyne incognita, m. javanica, or m. arenaria under greenhouse conditions where soil temperature ranged from 21 to 34 c. reproduction rates of all nematode species were high on all cultivars, except m. javanica and m. arenaria on 'brooks' and 'florida 501' oat. meloidogyne incognita and m. javanica produced more eggs on roots of 'rutgers' tomato than on cultivars of wheat, oat, rye, or barley. | 1989 | 19287666 |
| 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 |
| summer cropping effects on the abundance of meloidogyne arenaria race 2 and subsequent soybean yield. | a summer-planted crop of alyceelover significantly (p < 0.05) increased the soil abundance of meloidogyne arenaria race 2 juveniles by 3.7-fold when measured in the following spring. maize, sorghum, and soybean had no significant effects on residual nematode numbers over the same period. summer plantings of aeschynomene, cotton, hairy indigo, tespedeza, millet, peanut, and sorghum-sudangrass were as efficient as fallow in reducing root-knot nematode population levels. soybean yields (averaging 2 ... | 1993 | 19279844 |
| morphometric evaluation of hypotriploid and triploid populations of meloidogyne arenaria. | a morphometric comparison of seven hypotriploid populations with five pooled triploid populations of meloidogyne arenaria was made using standard descriptive statistics, stepwise discriminant analysis (sda), and cluster analysis. six morphometric characters of females, 14 of second-stage juveniles (j2), and 18 of males were measured for each population. useful differentiating characters included: body length in j2; stylet length in females and j2; stylet-knob dimensions in females and males; dor ... | 1993 | 19279751 |
| soybean-peanut rotations for the management of meloidogyne arenaria. | rotating soybean (glycine max cv. kirby) with peanut (arachis hypogaea cv. florunner) for managing meloidogyne arenaria race 1 was studied for 3 years (1985-87) in a field near headland, alabama. each year soybean plots had lower soil numbers of m. arenaria second-stage juveniles (j2) at peanut harvest than did plots in peanut monocnlture. peanut following either 1 or 2 years of soybean resulted in approximately 50% reduction in j2 soil population densities and a 14% (1-year soybean) or 20% (2-y ... | 1988 | 19290309 |
| soybean response to two isolates of meloidogyne arenaria. | | 1988 | 19290218 |
| 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 |
| field evaluation of selected soybean cultivars for resistance to two races of meloidogyne arenaria. | the soybean cultivars 'braxton' and 'kirby' were less susceptible to both races 1 and 2 of meloidogyne arenaria than 'centennial' and 'young', which were highly susceptible. soybean seed yields of resistant cultivars were greater (p = 0.05) than susceptible cultivars. reproduction of m. arenaria races 1 and 2 was significantly lower on less susceptible cultivars compared to highly susceptible cultivars. root galling, caused by m. arenaria, was 5-10 times greater on centennial and young than on l ... | 1992 | 19283054 |
| 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 |
| a rapid and efficient method for the screening of acid phosphatase 1 in young tomato seedlings, and for the identification of root-knot nematode species using miniaturized polyacrylamide gel electrophoresis. | a relatively rapid and highly sensitive miniaturized polyacrylamide gel electrophoresis technique is described for the analysis of certain isozymes from single cotyledons of tomato seedlings and from single females of the root-know nematode (meloidogyne spp.). homogenates from single tomato cotyledons (7, 14, 21, and 28 days old) were electrophoresed and stained for acid phosphatase 1 (aps 1) activity. cotyledons from plants of all the above age groups showed good aps 1 activity. nondestructive ... | 1992 | 1382970 |
| damage functions for meloidogyne arenaria on peanut. | microplot experiments were conducted in 1989 and 1990 to determine the relationship between yield of peanut (arachis hypogaea) and inoculum density ofmeloidogyne arenaria race 1. nine inoculum densities were used, ranging from 0-200 eggs/100 cm(3) soil (1989) or from 0-100 eggs/100 cm(3) (1990), and each density was replicated 10 times. in 1989, higher final densities (mean of 1,171 juveniles [j2]/100 cm(3) soil) were obtained in plots inoculated with 0.5 to 50 eggs/100 cm(3) soil than in plots ... | 1992 | 19283223 |
| soybean yield as related to rates of 1,3-dichloropropene applied at planting for management of root-knot disease. | 1,3-dichloropropene (1,3-d) at rates of 17.2 to 51.6 liters/ha applied 3 days preplant or at planting significantly (p < 0.05) reduced the amount of galling on roots of soybean grown in sites infested with meloidogyne incognita or m. arenaria. populations of m. incognita second-stage juveniles at harvest were significantly (p < 0.05) reduced by all treatments. only the 51.6-liters/ ha treatments and a 3-day preplant 34.4-liters/ha application significantly reduced at-harvest juvenile infestation ... | 1986 | 19294212 |
| relative damage functions and reproductive potentials of meloidogyne arenaria and m. hapla on peanut. | the reproductive potential and damage functions for meloidogyne hapla and m. arenaria race 1 on virginia-type peanuts (arachis hypogaea cv. florigiant) were determined over 2 years in microplot experiments in north carolina. peanut yield suppression and damage to pods as a result of galling were greatest in response to m. arenaria (p = 0.01). damage functions for the two species were adequately described by the quadratic models: yield (g/plot) = 398 - 17.1 (log[pi + 1]) - 17.0(log[pi + 1])(2); ( ... | 1992 | 19283222 |
| a novel technique for infesting field sites with encapsulated eggs of meloidogyne spp. | eggs of meloidogyne arenaria race 1 were encapsulated in calcium alginate for use as inoculum to infest peanut field plots. some eggs within the capsules remained viable up to 10 weeks after preparation. a field site was successfully infested at peanut planting and (or) 6 weeks later. dual applications of nematode inoculum (at planting and 6 weeks later) were superior to single applications (at planting or 6 weeks after planting). field-site infestation levels at the end of the first year were r ... | 1992 | 19283221 |
| genomic rflp analysis of meloidogyne arenaria race 2 populations. | traditional morphological methods of meloidogyne identification have been unsuccessful in distinguishing three south carolina, usa meloidogyne arenaria race 2 populations-govan, pelion, and florence. these populations differ greatly in reproductive rate and aggressiveness on soybean hosts. total genomic dna from eggs of each population was digested with the restriction endonuclease eco ri and southern hybridization analyses were performed with single-copy and interspersed multi-copy cloned probe ... | 1992 | 19283197 |
| characterization of potentially functional 5s rrna-encoding genes within ribosomal dna repeats of the nematode meloidogyne arenaria. | in the plant-parasitic nematode meloidogyne arenaria, isolated rdna repeats show length heterogeneity, and are unusual in that they contain putative 5s ribosomal rna pseudogenes [vahidi et al., j. mol. evol. 27 (1988) 222-227]. potentially functional 5s rrna-encoding genes can also be identified in various rdna repeats, which appear to be tandemly organized in the genome. | 1991 | 1748312 |
| comparison of winter and spring soil fumigation with 1,3-d for the management of meloidogyne arenaria on peanut. | field experiments were conducted in which the fumigant 1,3-d was applied at broadcast rates of 56 and 112 liters/ha during late winter and spring to two differing soil types in north florida. no advantage was demonstrated in applying the fumigant at the higher rate for the management of meloidogyne arenaria on peanut, and there was no disadvantage to applying a standard rate of the fumigant during winter as opposed to the standard practice of a 2-week preplant treatment. at one site, where rainf ... | 1991 | 19283185 |
| meloidogyne arenaria populations on soybean. | the distribution of meloidogyne spp. was determined in the piedmont and coastal plains soybean production areas of south carolina. meloidogyne arenaria, m. incognita, and m. javanica were found in six of seven counties surveyed, with some populations consisting of two or more species. because m. arenaria populations did not reproduce on peanut (arachis hypogaea cv. florunner), they were designated as host race 2. severity of root galling, shoot and root growth, seed yield, and nematode reproduct ... | 1991 | 19283177 |
| effects of pangola,digitgrass on meloidogyne arenaria, m. javanica, and m. hapla. | | 1983 | 19295862 |
| identification of meloidogyne species on the basis of head shape and, stylet morphology of the male. | head shape and stylet morphology of males of 90 populations of m. arenaria, m. hapla, m. incognita, and m. javanica from geographic regions of the world were compared by light microscopy (lm). in addition, stylets of one population each of m. arenaria, m. incognita, and m. javanica and three different chromosomal forms of m. hapla race a and two of race b were excised and examined with a scanning electron microscope (sem). differences among species occurred in both head and stylet morphology. he ... | 1981 | 19300797 |
| enhancement of cylindrocladium crotalariae root rot by meloidogyne arenaria (race 2) on a peanut cultivar resistant to both pathogens. | two populations of meloidogyne arenaria (race 2, incompatible on peanut) enhanced development of cylindrocladium black rot (cbr) on cbr-resistant peanut cv. nc 3033 in greenhouse factorial experiments. nematode populations 256 and 486 (0, 10(3), 10 eggs per 15-cm pot) were tested in all combinations with cylindrocladium crotalariae (0, 0.5, 5, 50 microsclerotia per cm(3) of soil). root-rot index increased in the presence of either population. positions but not slope values of inoculum density-di ... | 1981 | 19300770 |
| interaction between meloidogyne arenaria and glomus fascicuqlatus in grape. | root zones of grape (fitis vinifera cv thompson seedless) cuttings were infested with chlamydospores of glomus fasciculatus or eggs of meloidogyne arenaria or both. growth of grapevines was greatest in mycorrhizal (g. fasciculatus) plants. mycorrhizal development and growth of mycorrhizal and nonmycorrhizal plants were reduced in the presence of m. arenaria. at low initial nematode inoculum (pi) levels (approx. 200 eggs/plant), the presence of mycorrhizae enhanced plant growth during 1 yr, but n ... | 1981 | 19300722 |
| quantitative aspects of the development of meloidogyne arenaria larvae in grapevine varieties and rootstocks. | the development and productivity of parasitic stages of meloidogyne arenaria were quantitatively defined in 14 varieties or rootstocks of grapevine. mean development to maturity was related linearly to the number of degree-hours above 10 c temperature experienced from the time of penetration in all cultivars in which nematode adulthood was achieved. averaged across varieties, 13,142 heat units were required for development of the mean individual to maturity. the standard deviation of the develop ... | 1979 | 19305553 |
| modification of a computer simulation model for a plant-nematode system. | new data on egg development and death rates, and refinements of logic concerning interaction of the nematode and host, were incorporated into a simulation model of a meloidogyne arenaria and grapevine system. simulations of field data improved but other areas of weakness in the model were discovered. two peaks in the egg population curve suggested that the nematode was able to complete two life cycles before host dormancy and declining temperatures limited physiological activity. | 1978 | 19305839 |