| an aphelenchoides sp. nematode parasitic of polianthes tuberosa in the mekong delta. | polianthes tuberosa is a commercially valuable flower crop in the mekong delta of vietnam that is propagated by the harvesting and planting of bulbs. the cultivation of p. tuberosa is complicated by an endemic nematode infection that damages a high proportion of the plants. based on morphological criteria and ribosomal rna gene sequencing, we have determined that the infection is caused by an aphelenchoides sp. nematode and is most likely aphelenchoides besseyi. by scoring various parts of harve ... | 2007 | 19259495 |
| 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 |
| a simple method for determining aphelenchoides besseyi infestation level of oryza sativa seeds. | a simple extraction method was developed for obtaining the white tip nematode, aphelenchoides besseyi christie, from single seeds of rice, oryza sativa. the method was as follows: individual rice seeds were split longitudinally and then transferred into single pipet tips. tips containing a split seed were then singly placed upright in glass vials with water to extract the nematodes. this method was more efficient than the baermann funnel technique and allowed nearly 100% recovery of living a. be ... | 1999 | 19270929 |
| effect of water-soaking and air-drying on survival of aphelenchoides besseyiinoryza sativa seeds. | several nematicides have been used to disinfest rice seeds contaminated with the white tip nematode, aphelenchoides besseyi. we measured the efficacy of a standard disinfestation treatment that consists of soaking seeds in an aqueous emulsion of fenitrothion or fenthion and subsequently air-drying the seeds. we also measured the efficacy of the same treatments but without addition of nematicide to the soak water. viability was monitored at key points during treatment. our results showed that nem ... | 2000 | 19270981 |
| 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 |
| the purl gene of bacillus subtilis is associated with nematicidal activity. | parasitic nematodes of plants are important plant pathogens that represent a significant financial burden on agriculture. this study evaluated the efficacy of bacillus spp. as nematode biocontrol agents and identified bacillus genes associated with nematicidal activity. culture by products of bacillus subtilis strains okb105 and 69 and bacillus amyloliquefaciens strains fzb42 and b3 were used to treat aphelenchoides besseyi, ditylenchus destructor, bursaphelenchus xylophilus and meloidogyne java ... | 2011 | 21671997 |
| probability of detecting nematode infestations for quarantine sampling with imperfect extraction efficacy. | for quarantine sampling, it is of fundamental importance to determine the probability of finding an infestation when a specified number of units are inspected. in general, current sampling procedures assume 100% probability (perfect) of detecting a pest if it is present within a unit. ideally, a nematode extraction method should remove all stages of all species with 100% efficiency regardless of season, temperature, or other environmental conditions; in practice however, no method approaches the ... | 2011 | 22791911 |
| arabidopsis thaliana as a suitable model host for research on interactions between plant and foliar nematodes, parasites of plant shoot. | the rice white tip nematode (rwtn), aphelenchoides besseyi and the chrysanthemum foliar nematode (cfn), aphelenchoides ritzemabosi are migratory plant parasitic nematodes that infect the aboveground parts of plants. in this research, arabidopsis thaliana was infected by rwtn and cfn under indoor aseptic cultivation, and the nematodes caused recognizable symptoms in the leaves. furthermore, rwtn and cfn completed their life cycles and proliferated. therefore, a. thaliana was identified as a new h ... | 2016 | 27910895 |
| complete mitochondrial genomes of four entomopathogenic nematode species of the genus steinernema. | nematodes belonging to the genus steinernema are insect parasites and are used as effective biological agents against soil-dwelling insect pests. although the full nuclear genomes of multiple steinernema species have become available recently, mitochondrial genome information for the genus is limited. in this study, we sequenced the complete mitochondrial genomes of four species of steinernema and analysed their structure, codon usage and phylogenetic relationships. | 2016 | 27494995 |
| calreticulin is required for responding to stress, foraging, and fertility in the white-tip nematode, aphelenchoides besseyi. | calreticulin (crt) regulates a wide array of cellular responses in physiological and pathological processes. a full-length cdna-encoding crt protein, namely abcrt-1, was isolated from aphelenchoides besseyi, an ectoparasitic plant nematode and the agent of white tip disease of rice. the deduced amino acid sequence of abcrt-1 was highly homologous with other nematode crts, and showed the closest evolutionary relationship with bxcrt-1. in-situ hybridization showed that abcrt-1 is specifically loca ... | 2015 | 25999293 |
| genetic analysis and qtl detection for resistance to white tip disease in rice. | the inheritance of resistance to white tip disease (wtdr) in rice (oryza sativa l.) was analyzed with an artificial inoculation test in a segregating population derived from the cross between tetep, a highly resistant variety that was identified in a previous study, and a susceptible cultivar. three resistance-associated traits, including the number of aphelenchoides besseyi (a. besseyi) individuals in 100 grains (na), the loss rate of panicle weight (lrpw) and the loss rate of the total grains ... | 2014 | 25162680 |
| transcriptomic analysis of the rice white tip nematode, aphelenchoides besseyi (nematoda: aphelenchoididae). | the rice white tip nematode aphelenchoides besseyi, a devastating nematode whose genome has not been sequenced, is distributed widely throughout almost all the rice-growing regions of the world. the aims of the present study were to define the transcriptome of a. besseyi and to identify parasite-related, mortality-related or host resistance-overcoming genes in this nematode. | 2014 | 24637831 |
| nematicidal activity of fluensulfone against some migratory nematodes under laboratory conditions. | the fluoroalkenyl fluensulfone, known to have strong nematicidal activity against meloidogyne spp. (root-knot nematodes), was evaluated in vitro and in soil against the migratory nematodes bursaphelenchus xylophilus, aphelenchoides besseyi, aphelenchoides fragariae, ditylenchus dipsaci, pratylenchus penetrans, pratylenchus thornei and xiphinema index. | 2014 | 24452922 |
| early embryogenesis and anterior-posterior axis formation in the white-tip nematode aphelenchoides besseyi (nematoda: aphelenchoididae). | we followed the early embryogenesis of aphelenchoides besseyi from fertilization to the 4-cell stage under nomarski optics and examined the chromosome number and structure by dapi staining. after an oocyte is fertilized by a sperm, the eggshell forms and the male and female pronuclei are reconstructed. the male pronucleus moves toward the female pronucleus, which is located at the center of the egg. they meet, rotate 90°, and fuse. the embryo then divides unequally into a larger anterior ab cell ... | 2009 | 22661773 |
| an updated list of the plants associated with plant-parasitic aphelenchoides (nematoda: aphelenchoididae) and its implications for plant-parasitism within this genus. | few aphelenchoides spp. are facultative plant-parasites (foliar and bulb nematodes); three of them are well known in agricultural systems, namely aphelenchoides besseyi, a. fragariae and a. ritzemabosi. ten other plant-parasitic species, a. arachidis, a. bicaudatus, a. blastophthorus, a. dalianensis, a. ensete, a. nechaleos, a. paranechaleos, a. saprophilus, a. sphaerocephalus and a. subtenuis, have been reported from a limited number of plant species. we compiled a new database of the associate ... | 2015 | 26623893 |
| glycoside hydrolase (gh) 45 and 5 candidate cellulases in aphelenchoides besseyi isolated from bird's-nest fern. | five aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. two different glycoside hydrolase (gh) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. a abe gh5-1 gene containing an scp-like family domain was found only in the fern isolates. abe gh5-1 gene has five introns suggesting a eukaryotic origin. a maximum likelihood phylogeny revealed that abe gh5-1 is part of the nemato ... | 2016 | 27391812 |
| observations on the foliar nematode, aphelenchoides besseyi, infecting tuberose and rice in india. | the foliar nematode aphelenchoides besseyi causes white tip disease in rice (oryza sativa l.) and floral malady in tuberose (polianthes tuberosa l.). this nematode is widely distributed in the rice fields of many states of india, including west bengal (wb), andhra pradesh (ap), madhya pradesh (mp) and gujarat (gt). in order to generate information on intraspecific variations of a. besseyi as well as to confirm the identity of the nematode species infecting these important crops, morphological ob ... | 2012 | 23482906 |
| [discrimination and spectral response characteristic of stress leaves infected by rice aphelenchoides besseyi christie]. | an asd field spec pro full range spectrometer was used to acquire the spectral reflectance of healthy and diseased leaves infected by rice aphelenchoides besseyi christie, which were cut from rice individuals in the paddy field. firstly, foliar pigment content was investigated. as compared with healthy leaves, the total chlorophyll and carotene contents (mg x g(-1)) of diseased leaves decreased 18% and 22%, respectively. the diseased foliar content ratio of total chlorophyll to carotene was near ... | 2010 | 20496693 |
| extracting the rice white-tip nematode, aphelenchoides besseyi, with match sticks. | | 1976 | 19308217 |
| vertical migration of the rice white-tip nematode, aphelenchoides besseyi. | in the laboratory, the vertical migration of aphelenchoides besseyi was favored by rough surfaces and an inverse water gradient. in relation th gravity, the nematode migrated down or up equally, a circumstance suggesting that a geotaxis was not involved. stems of rice seedlings were effective surfaces for vertical migration of nematodes only when the stems were continuously supplied with moisture. | 1976 | 19308213 |
| occurrence of aphelenchoides besseyi in louisiana rice seed and its interaction with sclerotium oryzae in selected cultivars. | aphelenchoides besseyi, the nematode causal agent of white-tip disease of rice, was recovered from 5.5% of 474 seed samples obtained from rice seed warehouses in louisiana. laboratory tests in which a. besseyi-infested rice seed was treated with phostoxin(r), a compound used for control of insects in stored grain, indicate that it also has nematicidal properties. in 18-week-duration greenhouse tests, populations of a. besseyi increased 4-5-fold on the cultivars saturn and melrose and 3-fold on n ... | 1984 | 19295876 |
| conventional and pcr detection of aphelenchoides fragariae in diverse ornamental host plant species. | a pcr-based diagnostic assay was developed for early detection and identification of aphelenchoides fragariae directly in host plant tissues using the species-specific primers afragfl and afragrl that amplify a 169-bp fragment in the internal transcribed spacer (its1) region of ribosomal dna. these species-specific primers did not amplify dna from aphelenchoides besseyi or aphelenchoides ritzemabosi. the pcr assay was sensitive, detecting a single nematode in a background of plant tissue extract ... | 2007 | 19259510 |
| sexual compatibility among different host-originated isolates of aphelenchoides besseyi and the inheritance of the parasitism. | nine isolates of aphelenchoides besseyi from two different hosts were studied. the isolates were identified at the species level according to morphometrics and fine structures observed under a scanning electron microscope. two fern-originated isolates, fu, and fm, one rice-originated isolate, rl, were not able to reproduce from a single juvenile, based on at least 50 replicates. the other six isolates were able to develop into a small population when inoculated with a single juvenile, demonstrat ... | 2012 | 22815854 |
| molecular characterization and functions of fatty acid and retinoid binding protein gene (ab-far-1) in aphelenchoides besseyi. | rice white tip nematode, aphelenchoides besseyi, is a kind of plant parasitic nematodes that cause serious losses in rice and many other crops. fatty acid and retinoid binding protein (far) is a specific protein in nematodes and is related to development, reproduction, infection to the host, and disruption of plant defense reactions, so the inhibition of far function is the potential approach to control a. besseyi. the full-length of ab-far-1 cdna is 805 bp, including 546 bp of orf that encodes ... | 2013 | 23755297 |
| top 10 plant-parasitic nematodes in molecular plant pathology. | the aim of this review was to undertake a survey of researchers working with plant-parasitic nematodes in order to determine a 'top 10' list of these pathogens based on scientific and economic importance. any such list will not be definitive as economic importance will vary depending on the region of the world in which a researcher is based. however, care was taken to include researchers from as many parts of the world as possible when carrying out the survey. the top 10 list emerging from the s ... | 2013 | 23809086 |
| molecular characterization and development of real-time pcr assay for pine-wood nematode bursaphelenchus xylophilus (nematoda: parasitaphelenchidae). | bursaphelenchus xylophilus, the pine-wood nematode (pwn), is the causal agent of pine wilt disease, one of the most damaging emerging pest problems to forests around the world. it is native to north america where it causes relatively minor damage to native conifers but is labeled an eppo-a-2 pest and a quarantine nematode for many countries outside of the united states because of its potential for destruction to their native conifers. exports of wood logs and commodities involving softwood packa ... | 2013 | 24244367 |