| specific herbivore-induced volatiles defend plants and determine insect community composition in the field. | in response to insect attack, plants release complex blends of volatile compounds. these volatiles serve as foraging cues for herbivores, predators and parasitoids, leading to plant-mediated interactions within and between trophic levels. hence, plant volatiles may be important determinants of insect community composition. to test this, we created rice lines that are impaired in the emission of two major signals, s-linalool and (e)-β-caryophyllene. we found that inducible s-linalool attracted pr ... | 2012 | 22804824 |
| genetic dissection of sympatric populations of brown planthopper, nilaparvata lugens (stål), using dalp-pcr molecular markers. | direct amplified length polymorphism (dalp) combines the advantages of a high-resolution fingerprint method and also characterizing the genetic polymorphisms. this molecular method was also found to be useful in brown planthopper, nilaparvata lugens species complex for the analysis of genetic polymorphisms. a total of 11 populations of nilaparvata spp. were collected from 6 locations from malaysia. two sympatric populations of brown planthopper, n. lugens, one from rice and the other from a weed ... | 2012 | 22593700 |
| | the chemical pesticide, imidacloprid (imi) has long-lasting effectiveness against hemiptera. imi is commonly used to control the brown planthopper (bph), nilaparvata lugens stål (hemiptera: delphacidae). some chemical pesticides, however, can induce the susceptibility of rice to bph, which has indirectly led to the resurgence of bph. the mechanism of the chemical induction of the susceptibility of rice to bph was not previously understood. here, a 44 k agilent rice expression microarray was used ... | 2012 | 22544984 |
| de novo intestine-specific transcriptome of the brown planthopper nilaparvata lugens revealed potential functions in digestion, detoxification and immune response. | the brown planthopper (nilaparvata lugens, bph) is the most serious rice plant pests in asia. in this study, we performed transcriptome-wide analysis on bph intestine. we obtained more than 26 million sequencing reads that were then assembled into 53,553 unigenes with a mean size of 388 bp. based on similarity search with the nucleotide sequences available at ncbi, bph intestine-specific transcriptome analysis identified 21,405 sequences. assembled sequences were annotated with gene description, ... | 2012 | 22361737 |
| food assimilated by two sympatric populations of the brown planthopper nilaparvata lugens (delphacidae) feeding on different host plants contaminates insect dna detected by rapd-pcr analysis. | contamination of insect dna for rapd-pcr analysis can be a problem because many primers are non-specific and dna from parasites or gut contents may be simultaneously extracted along with that of the insect. we measured the quantity of food ingested and assimilated by two sympatric populations of brown planthopper (bph), nilaparvata lugens, one from rice and the other from leersia hexandra (poaceae), a wetland forage grass, and we also investigated whether host plant dna contaminates that of herb ... | 2012 | 22290463 |
| can tropical insects stand the heat? a case study with the brown planthopper nilaparvata lugens (stål). | the brown planthopper nilaparvata lugens (stål) is the most serious pest of rice across the world, especially in tropical climates. n. lugens nymphs and adults were exposed to high temperatures to determine their critical thermal maximum (ct(max)), heat coma temperature (hct) and upper lethal temperature (ult). thermal tolerance values differed between developmental stages: nymphs were consistently less heat tolerant than adults. the mean (± se) ct(max) of nymphs and adult females and males were ... | 2012 | 22253720 |
| mining and characterization of sequence tagged microsatellites from the brown planthopper nilaparvata lugens. | the brown planthopper, nilaparvata lugens (stål) (hemiptera: delphacidae), is an important pest of rice. to better understand the migration pattern and population structure of the chinese populations of n. lugens, we developed and characterized 12 polymorphic microsatellites from the expressed sequence tags database of n. lugens. the occurrence of these simple sequence repeats was assessed in three populations collected from three provinces of china. the number of alleles per locus ranged from 3 ... | 2011 | 22243416 |
| antifeedant and insecticidal effects of mandelic acid on the brown planthopper nilaparvata lugens stål. | to study the effects of mandelic acid (ma) on the brown planthopper (bph), nilaparvata lugens, the survival rate and behaviour of bph fed on an artificial diet with different dosages of ma was observed. the survival rate of bph decreased with the increase of the ma concentration and feeding time. in contrast to the control, the survival rate of bph 72 h after feeding decreased significantly. electrical penetration graph (epg) data indicated that ma absorbed by the rice plant from kimura b soluti ... | 2012 | 22191216 |
| population forecasting model of nilaparvata lugens and sogatella furcifera (homoptera: delphacidae) based on markov chain theory. | nilaparvata lugens (stål) and sogatella furcifera (horváth) are the two most important long-distance migratory insect pests that cause great yield losses to rice in china. accurate long-term population forecast is needed to implement effective management strategies for these two rice pests. in this paper, a transition probability matrix of 5-yr steps of markov chain theory was constructed based on 31-yr light-trapping data of the two pests from 1977 to 2007 in jiangkou county, guizhou, china. th ... | 2010 | 22182537 |
| are outbreaks of nilaparvata lugens (stål) associated with global warming? | outbreaks of the nilaparvata lugens (stål), have occurred frequently in china during the past few years, resulting in a broad and significant reduction in rice yield. n. lugens immigrate into china each spring from southeast asia, and the guangxi zhuang autonomous region is the first area affected. light trap catches for the early season period (march-june) in guangxi for the past 30 yr have been analyzed, and the catch sequences for five observation stations (longzhou, hepu, yongning yongfu, an ... | 2010 | 22182533 |
| microarray analysis of broad-spectrum resistance derived from an indica cultivar rathu heenati. | rathu heenati (rht) is a sri lankan rice cultivar that carries a brown planthopper (bph) resistance gene, bph3, and shows broad-spectrum resistance to all four biotypes of bph. the bph-resistance loci in rht has been studied extensively and assigned to four different rice chromosomes (3, 4, 6, and 10) by different research groups, but the gene has not been cloned previously. an affymetrix rice genome array containing 48,564 japonica and 1,260 indica sequences was used to analyze the potential re ... | 2012 | 22083132 |
| overexpression of a cytochrome p450 monooxygenase, cyp6er1, is associated with resistance to imidacloprid in the brown planthopper, nilaparvata lugens. | the brown planthopper, nilaparvata lugens, is an economically significant pest of rice throughout asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. the resistance of field populations of n. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome p450 monooxygenases (p450s), although, to date, the causative p450(s) has (have) not been identified. in the present study, biochemical assays using the model substrate 7-ethoxycoum ... | 2011 | 21929695 |
| development and use of est-ssr markers for assessing genetic diversity in the brown planthopper (nilaparvata lugens stål). | to assess genetic diversity in populations of the brown planthopper (nilaparvata lugens stål) (homoptera: delphacidae), we have developed and applied microsatellite, or simple sequence repeat (ssr), markers from expressed sequence tags (ests). we found that the brown planthopper clusters of ests were rich in ssrs with unique frequencies and distributions of ssr motifs. three hundred and fifty-one est-ssr markers were developed and yielded clear bands from samples of four brown planthopper popula ... | 2012 | 21896240 |
| differential resistance and cross-resistance to three phenylpyrazole insecticides in the planthopper nilaparvata lugens (hemiptera: delphacidae). | cross-resistance to two fipronil analogs, butene-fipronil and ethiprole, was detected in fipronil-resistant field populations and a resistant laboratory strain of the planthopper nilaparvata lugens (stål) (hemiptera: delphacidae), although the two analogs have not been used widely in rice-growing areas in china. the results showed that six field populations with 23.8-43.3-fold resistance to fipronil had reached a higher level of cross-resistance to ethiprole (resistance ratio [rr] = 47.1-100.9-f ... | 2011 | 21882705 |
| proteomic analysis of insecticide triazophos-induced mating-responsive proteins of nilaparvata lugens stål (hemiptera: delphacidae). | the brown planthopper, nilaparvata lugens (stål) (hemiptera: delphacidae), is a classic example of a resurgent pest induced by insecticides. it has been demonstrated that triazophos treatment causes an increase in the content of male accessory gland proteins (acps) that can be transferred to females via mating, influencing female reproduction. however, the mechanism of this type of insecticide-induced acps in males and the subsequent stimulation of reproduction in females are not well understood ... | 2011 | 21800909 |
| brown planthopper (n. lugens stal) feeding behaviour on rice germplasm as an indicator of resistance. | the brown planthopper (bph) nilaparvata lugens (stal) is a serious pest of rice in asia. development of novel control strategies can be facilitated by comparison of bph feeding behaviour on varieties exhibiting natural genetic variation, and then elucidation of the underlying mechanisms of resistance. | 2011 | 21779386 |
| characterization of soluble and membrane-bound alkaline phosphatase in nilaparvata lugens and their potential relation to development and insecticide resistance. | two forms (soluble and membrane-bound) of alkaline phosphatases (alps) were found in the brown planthopper, nilaparvata lugens. in order to further study alps in n. lugens, two putative alp genes (nl-alp1 and nl-alp2) were identified in this pest. both nl-alp1 and nl-alp2 show approximately the same degree of sequence identity (40-50%) to other insect soluble and membrane-bound forms of alp. correlation of alp activity and mrna levels at different developmental stages, or following application o ... | 2011 | 21769927 |
| the effects of triazophos on the trehalose content, trehalase activity and their gene expression in the brown planthopper nilaparvata lugens (stål) (hemiptera: delphacidae). | a previous study demonstrated that the flight capacity of nilaparvata lugens adults treated with triazophos was enhanced significantly. however, the physiological and regulative mechanisms of the flight enhancement are not well understood. trehalose is a primary blood sugar in insects, and the enzyme trehalase is involved in energy metabolism. the present study investigated the effects of triazophos on the trehalose content, trehalase activity (soluble trehalase and membrane-bound trehalase) and ... | 2011 | 21760647 |
| bt rice expressing cry1ab does not stimulate an outbreak of its non-target herbivore, nilaparvata lugens. | in this study, the non-target effects of bt rice "kmd2" expressing a cry1ab protein on the performance of the brown planthopper (bph), nilaparvata lugens, over multiple generations were evaluated under laboratory and field conditions. in the laboratory, bph was reared to observe the impact of the bt rice as compared to its parental non-bt cultivar xiushui 11, while the population dynamics and oviposition performance of bph were investigated in the field. the survival of bph nymphs fed bt and non ... | 2012 | 21688166 |
| life table and population parameters of nilaparvata lugens stal. (homoptera: delphacidae) on rice. | survival and fertility characteristics of the brown planthopper (bph), nilaparvata lugens were assessed in the laboratory and field. life tables and population parameters of the bph were constructed in an environment with unlimited food supply and that was free of natural enemies. the highest mortality occurred in the immature stage, especially in the first and second instars. the life table analysis showed that the population density of bph decreased gradually. the survival ratio of male to fem ... | 2011 | 24575207 |
| effect of fipronil on brain and muscle ultrastructure of nilaparvata lugens (stål) (homoptera: delphacidae). | the ultrastructure of nilaparvata lugens brain cells was damaged by treatment at different fipronil concentrations. the cell showed swollen mitochondria and vacuolization, but no mitochondrial cristae. rough endoplasmic reticulum (rer) fragmentation and degranulation were seen. the dilatation of endoplasmic reticulum cisterns was very prominent, and the predominant lamellar rers were arranged chaotically. the golgi apparatus demonstrated obvious changes in configuration, as dilated with closed c ... | 2011 | 21497400 |
| cross-resistance of bisultap resistant strain of nilaparvata lugens and its biochemical mechanism. | the resistant (r) strain of the planthopper nilaparvata lugens (stål) selected for bisultap resistance displayed 7.7-fold resistance to bisultap and also had cross-resistance to nereistoxin (monosultap, thiocyclam, and cartap), chlorpyrifos, dimethoate, and malathion but no cross-resistance to buprofezin, imidacloprid, and fipronil. to find out the biochemical mechanism of resistance to bisultap, biochemical assay was done. the results showed that cytochrome p450 monooxygenases (p450) activity i ... | 2011 | 21404864 |
| rna interference in nilaparvata lugens (homoptera: delphacidae) based on dsrna ingestion. | an efficient and convenient rna interference (rnai) technique involving double-stranded rna (dsrna) ingestion is useful for gene function studies of non-model insects. | 2011 | 21370391 |
| electrical penetration graph evidence that pymetrozine toxicity to the rice brown planthopper is by inhibition of phloem feeding. | pymetrozine is a valuable novel insecticide for control of sucking insects, including the brown planthopper nilaparvata lugens (stål), one of the most serious pests on rice. this study was conducted to elucidate the action mechanisms of pymetrozine on the feeding behaviour of the planthopper. | 2011 | 21254329 |
| biological effects of rice harbouring bph14 and bph15 on brown planthopper, nilaparvata lugens. | brown planthopper (nilaparvata lugens stål; bph) resistance genes bph14 and bph15 have been introgressed singly or pyramided into rice variety minghui 63 (mh63). the antibiosis and antixenosis effects of these rice lines on bph and the expression of five p450 genes of bph regulated by these rice lines were investigated in this study. | 2011 | 21254325 |
| transcriptome analysis of the brown planthopper nilaparvata lugens. | the brown planthopper (bph) nilaparvata lugens (stål) is one of the most serious insect pests of rice in asia. however, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. genomic information for bph is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of bph. | 2010 | 21151909 |
| analysis of time- and concentration-mortality relationship of nitenpyram against different larval stages of nilaparvata lugens (hemiptera: delphacidae). | bioassay of nitenpyram was conducted on the planthopper nilaparvata lugens (stål) (hemiptera: delphacidae) in the laboratory by using the rice-stem dipping method. the resulting data were analyzed using the complementary log-log time-concentration-mortality modeling technique, yielding the parameters for time and concentration effects of nitenpyram against n. lugens instars. the lc50 values to instars i and ii estimated for 24, 48, and 72 h after treatment were 1.03, 0.27, and 0.11 mg/liter, res ... | 2010 | 21061966 |
| rice planting systems, global warming and outbreaks of nilaparvata lugens (stål). | brown planthopper (bph, nilaparvata lugens (stål)) is one of the most serious pests of rice in both temperate and tropical regions of east and south asia and has become especially problematic over the past few years. in order to analyze the effect of the change of rice cropping system on the population dynamics of bph, field surveys of the occurrence and distribution of bph were performed and other relevant data, including light trap data and ovary dissection data were collected in nearly 40 chi ... | 2011 | 20961467 |
| revealing different systems responses to brown planthopper infestation for pest susceptible and resistant rice plants with the combined metabonomic and gene-expression analysis. | brown planthopper (bph) is a notorious pest of rice plants attacking leaf sheaths and seriously affecting global rice production. however, how rice plants respond against bph remains to be fully understood. to understand systems metabolic responses of rice plants to bph infestation, we analyzed bph-induced metabolic changes in leaf sheaths of both bph-susceptible and resistant rice varieties using nmr-based metabonomics and measured expression changes of 10 relevant genes using quantitative real ... | 2010 | 20936879 |
| feeding-based rna interference of a trehalose phosphate synthase gene in the brown planthopper, nilaparvata lugens. | the brown planthopper, nilaparvata lugens, is the most devastating rice insect pest to have given rise to an outbreak in recent years. rna interference (rnai) is a technological breakthrough that has been developed as a powerful tool for studying gene function and for the highly targeted control of insect pests. here, we examined the effects of using a feeding-based rnai technique to target the gene trehalose phosphate synthase (tps) in n. lugens. the full-length cdna of n. lugens tps (nltps) is ... | 2010 | 20726907 |
| sugar transporter genes of the brown planthopper, nilaparvata lugens: a facilitated glucose/fructose transporter. | the brown planthopper (bph), nilaparvata lugens, attacks rice plants and feeds on their phloem sap, which contains large amounts of sugars. the main sugar component of phloem sap is sucrose, a disaccharide composed of glucose and fructose. sugars appear to be incorporated into the planthopper body by sugar transporters in the midgut. a total of 93 expressed sequence tags (ests) for putative sugar transporters were obtained from a bph est database, and 18 putative sugar transporter genes (nlst1-1 ... | 2010 | 20705135 |
| molecular cloning, transcriptional regulation, and differential expression profiling of vitellogenin in two wing-morphs of the brown planthopper, nilaparvata lugens stål (hemiptera: delphacidae). | the brown planthopper, nilaparvata lugens, is a serious pest of rice crops throughout asia and exhibits wing dimorphism, with brachypterous adults having reduced wings and macropterous adults possessing fully developed wings. to understand the reproductive strategies in two wing-morphs of this insect, the transcript encoding the major yolk protein precursor, vitellogenin (vg), was cloned. the complete mrna transcript was 6314 bp, which encodes a protein of 2063 residues including an 18-residue p ... | 2010 | 20698901 |
| high-resolution mapping of the brown planthopper resistance gene bph6 in rice and characterizing its resistance in the 9311 and nipponbare near isogenic backgrounds. | brown planthopper (nilaparvata lugens stål, bph) is one of the most destructive insect pests of rice. exploring resistance genes from diverse germplasms and incorporating them into cultivated varieties are critical for controlling this insect. the rice variety swarnalata was reported to carry a resistance gene (designated bph6), which has not yet been assigned to a chromosome location and the resistance mechanism is still unknown. in this study, we identified and mapped this gene using the f(2) ... | 2010 | 20680611 |
| laboratory and field assessments of prey-mediated effects of transgenic bt rice on ummeliata insecticeps (araneida: linyphiidae). | one major concern regarding the release of bt rice is its potential impact through tritrophic interactions on nontarget arthropods, especially natural enemies. we studied the effects of two bt transgenic rice varieties, tt9- 3 and kmd1, expressing cry1ab/cry1ac and cry1ab, respectively, on a predatory ground spider [ummeliata insecticeps (bösenberg et strand)] supplied with bt rice-fed brown planthopper [nilaparvata lugens (stål)] nymphs. although immunoassays confirmed that u. insecticeps inges ... | 2010 | 22127189 |
| two novel cytochrome p450 genes cyp6cs1 and cyp6cw1 from nilaparvata lugens (hemiptera: delphacidae): cdna cloning and induction by host resistant rice. | two novel full-length p450 cdnas, cyp6cs1 and cyp6cw1, were cloned from the fourth instar nymphs of brown planthopper nilaparvata lugens stål (hemiptera: delphacidae) reared on its susceptible rice variety taichung native 1 (tn1) plants. the deduced proteins are typical microsomal p450s sharing conserved structural and functional domains with other insect cyp6 members. temporal expression analysis by northern blot hybridization indicated pre-exposure to n. lugens moderately resistant rice minghu ... | 2011 | 20609275 |
| gene knockdown by intro-thoracic injection of double-stranded rna in the brown planthopper, nilaparvata lugens. | rna interference (rnai) is a powerful strategy for gene function study in insects. here, we described the development of a rnai technique by microinjection of double-stranded rna (dsrna) in the brown planthopper nilaparvata lugens. based on the mortality and rnai efficiency criteria, the conjunctive between prothorax and mesothorax was selected as the injection site and 50 nl as injection volume. three genes with different expression patterns were selected to evaluate the rnai efficiency. a comp ... | 2010 | 20599616 |
| [effects of azadirachtin on rice plant volatiles induced by nilaparvata lugens]. | with the method of solid phase microextraction (spme), a total of twenty-five volatiles were collected from rice plants induced by nilaparvata lugens, and after applying azadirachtin fourteen of them were qualitatively identified by gas chromatography coupled by mass spectrometry (gc-ms), mainly of nine kinds of sesquiterpenes. comparing with healthy rice plants, the plants attacked by n. lugens had more kinds of volatiles, including limonene, linalool, methyl salicylate, unknown 6, unknown 7, z ... | 2010 | 20387443 |
| triazophos up-regulated gene expression in the female brown planthopper, nilaparvata lugens. | the widespread use of insecticides has caused the resurgence of the brown planthopper, nilaparvata lugens, in asia. in this study, we investigated an organo-phosphorous insecticide, triazophos, and its ability to induce gene expression variation in female n. lugens nymphs just before emergence. by using the suppression subtractive hybridization method, a triazophos-induced cdna library was constructed. in total, 402 differentially expressed cdna clones were obtained. real-time qpcr analysis conf ... | 2010 | 20223245 |
| identification and characterization of bph14, a gene conferring resistance to brown planthopper in rice. | planthoppers are highly destructive pests in crop production worldwide. brown planthopper (bph) causes the most serious damage of the rice crop globally among all rice pests. growing resistant varieties is the most effective and environment-friendly strategy for protecting the crop from bph. more than 19 bph-resistance genes have been reported and used to various extents in rice breeding and production. in this study, we cloned bph14, a gene conferring resistance to bph at seedling and maturity ... | 2009 | 20018701 |
| native subunit composition of two insect nicotinic receptor subtypes with differing affinities for the insecticide imidacloprid. | neonicotinoid insecticides, such as imidacloprid, are selective agonists of insect nicotinic acetylcholine receptors (nachrs) and are used extensively to control a variety of insect pest species. the brown planthopper (nilaparvata lugens), an insect pest of rice crops throughout asia, is an important target species for control with neonicotinoid insecticides such as imidacloprid. studies with nachrs purified from n. lugens have identified two [(3)h]imidacloprid binding sites with different affin ... | 2010 | 20005950 |
| selectivity of lynx proteins on insect nicotinic acetylcholine receptors in the brown planthopper, nilaparvata lugens. | neuronal nicotinic acetylcholine receptors (nachrs) are major excitatory neurotransmitter receptors in both vertebrates and invertebrates. two lynx proteins (nl-lynx1 and nl-lynx2) have been identified in the brown planthopper, nilaparvata lugens, which act as modulators on insect nachrs. in the present study, two lynx proteins were found to act on the triplet receptor nlalpha1/nlalpha2/beta2 expressed in xenopus oocytes, increasing agonist-evoked macroscopic currents, but not changing agonist s ... | 2010 | 20002807 |
| [interactive effects of temperature and nitrogen fertilizer on the survival, development, and reproduction of brown planthopper nilaparvata lugens]. | a laboratory study was made on the interactive effects of temperature (20 degrees c, 23 degrees c, 26 degrees c, 29 degrees c, and 32 degrees c) and nitrogen fertilization level (0 and 250 kg x hm(-2)) on the survival, development, and reproduction of brown planthopper (bph) nilaparvata lugens. with increasing temperature from 20 degrees c to 29 degrees c, the egg hatchability, nymphal survival, and adult fecundity of bph increased and the developmental duration of all stages shortened; while at ... | 2009 | 19803177 |
| [resistance stability of rice varieties to different biotypes of brown planthopper]. | in order to develop an effective analytical and monitoring method in breeding rice varieties with higher resistance stability to brown planthopper (bph), tai's method (1971) was employed to estimate the resistance stability of twelve rice varieties to different biotypes of bph. it was shown that light intensity, seedling age, and nitrogen application rate had significant effects on the resistance performance and stability of rice varieties to different bph biotypes. among the varieties with resi ... | 2009 | 19795662 |
| insecticide-induced changes in protein, rna, and dna contents in ovary and fat body of female nilaparvata lugens (hemiptera: delphacidae). | the widespread use of insecticides is known to cause resurgence in nilaparvata lugens (stål) (hemiptera: delphacidae) populations, a serious insect pest of rice, orzya sativa l., crops in asia. the current study investigated insecticide-induced changes in protein, rna, and dna levels in the ovary and fat body of adult female n. lugens. potted rice plants were sprayed with different concentrations of imidacloprid, triazophos, and detamethrin. the results showed that all three insecticides caused ... | 2009 | 19736763 |
| high-resolution mapping of two rice brown planthopper resistance genes, bph20(t) and bph21(t), originating from oryza minuta. | brown planthopper (bph) is one of the most destructive insect pests of rice. wild species of rice are a valuable source of resistance genes for developing resistant cultivars. a molecular marker-based genetic analysis of bph resistance was conducted using an f(2) population derived from a cross between an introgression line, 'ir71033-121-15', from oryza minuta (accession number 101141) and a susceptible korean japonica variety, 'junambyeo'. resistance to bph (biotype 1) was evaluated using 190 f ... | 2009 | 19669727 |
| functional co-expression of two insect nicotinic receptor subunits (nlalpha3 and nlalpha8) reveals the effects of a resistance-associated mutation (nlalpha3) on neonicotinoid insecticides. | neonicotinoid insecticides, such as imidacloprid, are selective agonists of insect nicotinic acetylcholine receptors (nachrs) and are used extensively to control a variety of insect pest species. previously, we have identified a nachr point mutation (y151s) associated with insecticide resistance in the brown planthopper nilaparvata lugens. although this mutation has been identified in two different n. lugens nachr subunits (nlalpha1 and nlalpha3) because of difficulties in heterologous expressio ... | 2009 | 19627438 |
| characterization of putative soluble and membrane-bound trehalases in a hemipteran insect, nilaparvata lugens. | trehalose is the main blood sugar of insects, and the enzyme trehalase is involved in energy metabolism and controlling trehalose levels in cells. two forms (soluble and membrane-bound) of trehalase and the corresponding genes (nltre-1 and nltre-2) were identified from the brown planthopper, nilaparvata lugens. both nltre-1 and nltre-2 contain trehalase signature motifs, and nltre-2 contains a putative transmembrane domain. comparison of trehalase activity and gene mrna level at different develo ... | 2009 | 19615372 |
| understanding rice plant resistance to the brown planthopper (nilaparvata lugens): a proteomic approach. | engineering and breeding resistant plant varieties are the most effective and environmentally friendly ways to control agricultural pests and improve crop performance. however, the mechanism of plant resistance to pests is poorly understood. here we used a quantitative mass-spectrometry-based proteomic approach for comparative analysis of expression profiles of proteins in rice leaf sheaths in responses to infestation by the brown planthopper (nilaparvata lugens stål, bph), which is a serious ri ... | 2009 | 19405033 |
| antifeedants of indian barnyard millet, echinochloa frumentacea link, against brown planthopper, nilaparvata lugens (stål). | eight compounds isolated from indian barnyard millet have been identified as l-malic acid, trans-aconitic acid, (+)-isocitric acid, 5-o-caffeoylquinic acid, 4-o-caffeoylquinic acid, isocarlinoside, 2"-o-rhamnosylisoorientin, and 7-o-(2"-o-glucuronosyl)glucuronosyltricin, respectively. these compounds showed high antifeeding activity against brown planthopper only when they were combined. | 2016 | 19040117 |
| sublethal effects of four insecticides on the reproduction and wing formation of brown planthopper, nilaparvata lugens. | the brown planthopper (bph), nilaparvata lugens stål, is a major rice pest in many parts of asia. neonicotinoids such as imidacloprid and dinotefuran are widely used for control of this pest, and resistance to these insecticides has developed in recent years. this pest has also been widely exposed to triazophos and fenvalerate, although these insecticides are not used for the control of the pest directly. here, the effects of sublethal doses of these four insecticides on the reproduction and win ... | 2009 | 18937216 |
| species-specific insecticide resistance to imidacloprid and fipronil in the rice planthoppers nilaparvata lugens and sogatella furcifera in east and south-east asia. | in 2003 the development of insecticide resistance against neonicotinoids in the brown planthopper (bph), nilaparvata lugens (stål) (homoptera: delphacidae), was first observed in thailand and has since been found in other asian countries such as vietnam, china and japan. however, the ld(50) values of bph and the whitebacked planthopper (wbph), sogatella furcifera (horváth), against both neonicotinoid and phenylpyrazole insecticides have been poorly reported in many asian countries. | 2008 | 18803329 |
| neonicotinoid resistance in rice brown planthopper, nilaparvata lugens. | rice brown planthopper, nilaparvata lugens stål, is a primary insect pest of cultivated rice, and effective control is essential for economical crop production. resistance to neonicotinoid insecticides, in particular imidacloprid, has been reported as an increasing constraint in recent years. in order to investigate the extent of resistance, 24 samples of n. lugens were collected from china, india, indonesia, malaysia, thailand and vietnam during 2005 and 2006. their responses to two diagnostic ... | 2008 | 18803175 |
| susceptibility to neonicotinoids and risk of resistance development in the brown planthopper, nilaparvata lugens (stål) (homoptera: delphacidae). | in recent years, outbreaks of the brown planthopper, nilaparvata lugens (stål), have occurred more frequently in china. the objective of this study was to determine the susceptibility of n. lugens to neonicotinoids and other insecticides in major rice production areas in china. | 2008 | 18680157 |
| preference and performance of anagrus nilaparvatae (hymenoptera: mymaridae): effect of infestation duration and density by nilaparvata lugens (homoptera: delphacidae). | the effect of nilaparvata lugens (stål) infestation duration and density on the host preference and performance of anagrus nilaparvatae pang et wang, an egg parasitoid of rice planthoppers, was determined. the results showed that the parasitoid preferred n. lugens eggs on the plants infested with 10 gravid n. lugens females for 1 d to those plants infested with 10 gravid females for 2 or 3 d. it was also found to prefer n. lugens eggs on plants infested with 10 or 20 adult females after 24 h of ... | 2008 | 18559181 |
| molecular tagging of the bph1 locus for resistance to brown planthopper (nilaparvata lugens stål) through representational difference analysis. | during brown planthopper (bph) feeding on rice plants, we employed a modified representational difference analysis (rda) method to detect rare transcripts among those differentially expressed in snbc61, a bph resistant near-isogenic line (nil) carrying the bph1 resistance gene. this identified 3 rda clones: osbphi237, osbphi252 and osbphi262. dna gel-blot analysis revealed that the loci of the rda clones in snbc61 corresponded to the alleles of the bph resistant donor samgangbyeo. expression ana ... | 2008 | 18553105 |
| evidence of sibling species in the brown planthopper complex (nilaparvata lugens) detected from short and long primer random amplified polymorphic dna fingerprints. | the inheritance of 31 amplicons from short and long primer rapd was tested for segregating ratios in two families of the brown planthopper, nilaparvata lugens, and they were found to be inherited in a simple mendelian fashion. these markers could now be used in population genetics studies of n. lugens. ten populations of n. lugens were collected from five locations in malaysia. each location had two sympatric populations. cluster and principal coordinate analyses based on genetic distance along ... | 2008 | 18504649 |
| imidacloprid susceptibility survey and selection risk assessment in field populations of nilaparvata lugens (homoptera: delphacidae). | imidacloprid has been used for many years to control planthopper nilaparvata lugens (stål) (homoptera: delphacidae) in china. to provide resistance assessment for the national insecticide resistance management program, we collected a total of 42 samples of the planthoppers from 27 locations covering eight provinces to monitor their dose responses and susceptibility changes to imidacloprid over an 11-yr period (1996-2006). results showed that most field populations maintained susceptibility from ... | 2008 | 18459419 |
| cultivar and insecticide applications affect the physiological development of the brown planthopper, nilaparvata lugens (stål) (hemiptera: delphacidae). | nilaparvata lugens (stål) (hemiptera:delphacidae) is a serious migratory pest of rice in asia. pest resurgence often occurs because of insecticide overuse. using both susceptible (tn1) and moderately resistant (xieyou 963) cultivars, we studied the effect of foliar insecticides on the percentage of brachypterous adults, female reproductive rate, and crude fat and soluble sugar contents in third- and fifth-instar nymphs and adults. the percentage of brachypterous adults and reproductive rate of a ... | 2008 | 18348812 |
| the novel botanical insecticide for the control brown planthopper (nilaparvata lugens stal.). | brown planthopper, nilaparvata lugens stal., (bph) was the most devastating insect pest on rice in many parts of asia. the outbreak of bph? which is resistant to many synthetic insecticides can cause total rice crop loss. this research was done to evaluate the efficiency of mangostin from the pericarp of mangosteen fruit extract (garcina mangostana l.) as the alternative control of bph. the pericarp of mangosteen fruit was extracted by soxhlet apparatus using ethanol as a solvent and purified by ... | 2006 | 17385515 |
| differences in induced volatile emissions among rice varieties result in differential attraction and parasitism of nilaparvata lugens eggs by the parasitoid anagrus nilaparvatae in the field. | we compared the volatiles of ja-treated plants of six rice varieties and then determined, in the laboratory and field, if they differed in attractiveness to anagrus nilaparavate pand et wang, an egg parasitoid of rice planthoppers. analyses of volatiles revealed significant differences among varieties, both in total quantity and quality of the blends emitted. on the basis of these differences, the six varieties could be roughly divided into three groups. in a y-tube olfactometer, female wasps pr ... | 2006 | 17061169 |
| fitness costs of laboratory-selected imidacloprid resistance in the brown planthopper, nilaparvata lugens stål. | imidacloprid has been used as a key insecticide to control the brown planthopper, nilaparvata lugens stål, for several years, but no obvious resistance has been identified in field populations as yet. to evaluate the risk, a field population was collected and selected with imidacloprid in the laboratory. after 37-generation selection a strain with 250-fold resistance had been successfully achieved. fitness analysis by constructing life tables demonstrated that resistant hoppers had obvious disad ... | 2006 | 16475223 |
| genetic analysis and fine mapping of a rice brown planthopper (nilaparvata lugens stål) resistance gene bph19(t). | genetic analysis and fine mapping of a resistance gene against brown planthopper (bph) biotype 2 in rice was performed using two f(2) populations derived from two crosses between a resistant indica cultivar (cv.), as20-1, and two susceptible japonica cvs., aichi asahi and lijiangxintuanheigu. insect resistance was evaluated using f(1) plants and the two f(2) populations. the results showed that a single recessive gene, tentatively designated as bph19(t), conditioned the resistance in as20-1. a l ... | 2006 | 16395578 |
| identification of a rice gene (bph 1) conferring resistance to brown planthopper (nilaparvata lugens stal) using sts markers. | this study was carried out to identify a high-resolution marker for a gene conferring resistance to brown planthopper (bph) biotype 1, using japonica type resistant lines. bulked segregant analyses were conducted using 520 rapd primers to identify rapd fragments linked to the bph resistance gene. eleven rapds were shown to be polymorphic amplicons between resistant and susceptible progeny. one of these primers, ope 18, which amplified a 923 bp band tightly linked to resistance, was converted int ... | 2005 | 16258238 |
| attraction of the parasitoid anagrus nilaparvatae to rice volatiles induced by the rice brown planthopper nilaparvata lugens. | anagrus nilaparvatae, an egg parasitoid of the rice brown planthopper nilaparvata lugens, was attracted to volatiles released from n. lugens-infested plants, whereas there was no attraction to volatiles from undamaged plants, artificially damaged plants, or volatiles from n. lugens nymphs, female adults, eggs, honeydew, and exuvia. there was no difference in attractiveness between plants infested by n. lugens nymphs or those infested by gravid females. attraction was correlated with time after i ... | 2005 | 16195848 |
| exogenous application of jasmonic acid induces volatile emissions in rice and enhances parasitism of nilaparvata lugens eggs by the parasitoid anagrus nilaparvatae. | jasmonate signaling pathway plays an important role in induced plant defense against herbivores and pathogens, including the emission of volatiles that serve as attractants for natural enemies of herbivores. we studied the volatiles emitted from rice plants that were wounded and treated with jasmonic acid (ja) and their effects on the host-searching behavior of the rice brown planthopper, nilaparvata lugens (stål), and its mymarid egg parasitoid anagrus nilaparvatae pang et wang. female adults o ... | 2005 | 16132208 |
| [secondary compounds in rice varieties resistant to nilaparvata lugens]. | by the method of high-performance liquid chromatography (hplc), this paper studied the contents of 13 secondary compounds from 130 samples of 26 rice varieties resistant to brown planthopper (bph) nilaparvata lugens biotype ii. a prediction model was established through principal component analysis and multiple regression analysis: y = 3.4593 - 0.02491 x1 + 0.08475 x2 - 0.04227 x8 + 0.1174 x12. the relationships between the bph-resistant level of rice varieties and the area values of chromatogra ... | 2004 | 15707334 |
| changes of zeatin riboside content in rice plants due to infestation by nilaparvata lugens (homoptera: delphacidae). | the effect of nilaparvata lugens (stål) (homoptera: delphacidae), infestation on the content of zeatin ribosides (zr) in rice plants was investigated with enzyme-linked immunosorbent assay. hydroponics experiments were conducted on 'zhendao 2' rice, in which plants were subjected to n. lugens infestation at three nonhopperburn-causing densities (15, 30, and 60 nymphs per hill) for 2, 4, 6, and 8 d and at one hopperburn-causing density (240 nymphs per hill) for 2, 4, and 6 d, respectively. when r ... | 2004 | 15666745 |
| [isolation of rice genes down-regulated by brown planthopper infestation by suppression subtractive hybridization]. | suppression subtractive hybridization (ssh) was used to isolate rice genes down-regulated by bph infestation. the ssh cdna library constructed with the tester cdna from rice seedlings, and driver cdna from rice seedlings fed by bph consists of 200 clones. fifty clones were randomly picked and screened by reverse northern dot blot and northern blot. as a result, two cdna fragments have been isolated: one is lhca, which encodes rice photosystem i antenna protein; the other is a novel rice gene, an ... | 2004 | 15599027 |
| mechanisms of hopperburn: an overview of insect taxonomy, behavior, and physiology. | hopperburn is a non-contagious disease of plants caused by the direct feeding damage of certain leafhoppers and planthoppers. although long studied, especially with empoasca spp. leafhoppers (cicadellidae: typhlocybinae), the mechanisms underlying hopperburn have only recently been elucidated. hopperburn is caused by a dynamic interaction between complex insect feeding stimuli (termed hopperburn initiation) and complex plant responses (termed the hopperburn cascade). herein we review the nature ... | 2005 | 15471532 |
| molecular cloning and immunolocalization of a diuretic hormone receptor in rice brown planthopper (nilaparvata lugens). | rna extracted from guts of rice brown planthopper, nilaparvata lugens, was used to clone cdna predicted to encode a diuretic hormone receptor (dhr). the dhr, a member of the calcitonin/secretin/corticotropin-releasing factor family of g-protein-coupled receptors, contains seven transmembrane domains and a large n-terminal extracellular domain potentially involved in hormone binding. the n-terminal domain was expressed as a recombinant protein, purified and used to raise antibodies. anti-dhr igg ... | 2004 | 15373805 |
| proteomic analysis of brown planthopper: application to the study of carbamate toxicity. | toxicity to o-sec-butylphenyl methylcarbamate compound (bpmc) was analyzed in the rice brown planthopper, nilaparvata lugens, using a differential proteomics approach of identifying proteins on two dimensional-polyacrylamide gel electrophoresis (2d-page). proteome analysis from bpmc-treated brown planthopper resulted in the modulation of 22 proteins at the expression level as compared to control samples on coomassie brilliant blue (cbb) stained gels. out of total 22 proteins, 10 proteins showed ... | 2004 | 15110863 |
| differential gene expression in response to brown planthopper feeding in rice. | plant responses to herbivores are complex. 108 cdna clones representing genes relating to plant responses to chewing insect-feeding, pathogen infection, wounding and other stresses were collected. northern blot and cdna array analysis were employed to investigate gene expression regulated by piercing-sucking insect, brown planthopper (bph), nilaparvata lugens (homoptera: dephacidae) on both the resistant and susceptible rice genotypes. after bph feeding in rice for 72 h, the expression of most t ... | 2004 | 15002664 |
| do rice hybrids have heterosis for insect resistance? a study with nilaparvata lugens (hemiptera: delphacidae) and marasmia patnalis (lepidoptera: pyralidae). | antibiosis-based resistance to two insect pests of rice, nilaparvata lugens (stål) (hemiptera: delphacidae) and marasmia patnalis bradley (lepidoptera: pyralidae), was compared in 11 f1 hybrids and their parental lines. our objective was to determine whether hybrids show heterosis (hybrid vigor) for insect resistance or susceptibility. heterosis is defined as the amount by which a hybrid exceeds its midparent value or its better parent. overall, we did not find evidence of heterosis or heterobel ... | 2003 | 14977136 |
| nutrient uptake of rice roots in response to infestation of nilaparvata lugens (stål) (homoptera: delphacidae). | this study investigated the uptake of three macronutrients, including nitrogen (n), phosphorus (p), and potassium (k), by rice roots in response to different infestation levels of nilaparvata lugens (stål) (homoptera: delphacidae). hydroponics experiments were conducted on the rice variety 'zhendao 2' (moderately resistant to tryporyza incertulas, lepidoptera: pyralidae) and the variety 'xiushui 63' (susceptible to n. lugens). in 'zhendao 2', n. lugens infestation significantly influenced the up ... | 2003 | 14977118 |
| selection for imidacloprid resistance in nilaparvata lugens: cross-resistance patterns and possible mechanisms. | a field population of brown planthoppers (nilaparvata lugens stål) was collected and selected for imidacloprid resistance in the laboratory. the resistance increased by 11.35 times in 25 generations and the resistance ratio reached 72.83 compared with a laboratory susceptible strain. the selected resistant strain showed obvious cross-resistance to all the acetylcholine receptor targeting insecticides tested (monosultap 1.44-fold, acetamiprid 1.61-fold, imidacloprid homologues js599 2.46-fold and ... | 2003 | 14667058 |
| [chaotic diagnosis of nilaparvata lugens occurrence system]. | it is estimated that there are nearly 20 million hectares of rice crop being infested by nilaparvata lugens, with an annual loss of some half a million tones of grain. in order to study the properties and laws of nilaparvata lugens occurrence system further, the time series data of nilaparvata lugens occurrence from 1986 to 1998 collected in taihu lake district were analyzed by using the methods of autocorrelation function, power spectrum figure, phase trajectory figure, poincare section, and re ... | 2003 | 14655376 |
| enhancement of short wing formation and ovarian growth in the genetically defined macropterous strain of the brown planthopper, nilaparvata lugens. | when jh ii, iii or methoprene was applied in the nymphal stages to two different strains of the brown planthopper which were selected to produce long (macropterous) or short (brachypterous) wing forms, no effect was observed on the molting profile or metamorphosis. brachypterization of a majority of the presumptive macropters was, however, observed by application of these chemicals, although there was no effect on wing form in the presumptive brachypters. the results show that the sensitive peri ... | 1999 | 12770400 |
| sensitive periods for wing development and precocious metamorphosis after precocene treatment of the brown planthopper, nilaparvata lugens. | the critical periods for juvenile hormone suppression of wing development and metamorphosis were examined in a pure brachypterous line of nilaparvata lugens following topical application of precocene ii (pii) to various stages of the third and fourth nymphal stadia. when pii, in doses ranging from 10 pg to 100 ng, was applied to 12-h-old third or 6-h-old fourth stadium nymphs, long-wing formation (macroptery) was induced. macropter induction ranged from 5 to 50% in females and from 30 to 50% in ... | 2002 | 12770122 |
| [application of latent root regression method in analysis of predation of predatory natural enemy in paddy field]. | a latent root regression model was constructed for analyzing the predation quantity in a coexistence system of four spiders (pirata subpiraticus, oedothorax insecticeps, clubiona japonicola, and bianor hotingchiehi) with brown planthopper (nilaparvata lugens). the predation quantity of the spiders in a multi-species coexistence system could be predicted by y = 6.6600 +/- 6.3399(- 0.0138x1* + 0.0895x2. + 0.0078x3* - 0.1067x4* + 0.6742x5*). the result showed that compared to ls regression, the acc ... | 2002 | 12682962 |
| rflp-facilitated investigation of the quantitative resistance of rice to brown planthopper ( nilaparvata lugens). | quantitative trait loci (qtls), conferring quantitative resistance to rice brown planthopper (bph), were investigated using 160 f(11) recombinant inbred lines (rils) from the lemont/teqing cross, a complete rflp map, and replicated phenotyping of seedbox inoculation. the paternal indica parent, teqing, was more-resistant to bph than the maternal japonica parent, lemont. the rils showed transgressive segregation for resistance to bph. seven main-effect qtls and many epistatic qtl pairs were ident ... | 2002 | 12582694 |
| putative protein digestion in a sap-sucking homopteran plant pest (rice brown plant hopper; nilaparvata lugens: delphacidae)--identification of trypsin-like and cathepsin b-like proteases. | sap-sucking phytophagous insect species of the order hemiptera have been assumed not to carry out digestive proteolysis, but instead to rely on free amino acids in the phloem and xylem saps for their nutritional requirements. extracts prepared from isolated guts of rice brown planthopper (nilaparvata lugens), a homopteran crop pest, were shown to contain protease activity, with hydrolysis of both protein and synthetic peptide substrates being observed. assays with specific inhibitors suggested t ... | 2002 | 12213233 |
| electroantennogram responses of nilaparvata lugens (homoptera: delphacidae) to plant volatile compounds. | electroantennogram (eag) recordings were made from the plaque organ receptors of the rice brown plant hopper, nilaparvata lugens (stål). the receptors of the distal plaque organ of both male and female hoppers responded to the air from above chopped rice plants, and those of females gave a larger response. female hoppers, tested with 27 plant volatiles, gave dose-related responses to 16 of the compounds, including a range of green leaf volatiles. the aliphatic aldehydes hexanal and (e)-2-hexenal ... | 2002 | 12020000 |
| [effect of rice variety resistance on population dynamics of nilaparvata lugens and sogatella furcifera]. | the effect of rice varieties with different insect-resistance on dynamics of nilaparvata lugens and sogatella furcifera population was examined, based on the investigation of their inhabiting ratio, egg amount, survival rate of egg and nymph, nymph development, and the amount of their offspring population. four rice varieties, tn1, n22, asd7 and ptb33 were investigated. ptb33 had a significantly lower inhabiting ratio, egg amount, and survival ratio of eggs and nymphs of both parasitic populatio ... | 2000 | 11767559 |
| [tolerance of various geographic populations of brown planthopper to adverse environmental stresses]. | the populations of brown planthopper(bph), nilaparvata lugens, were collected from zhejiang, guangxi and yunnan provinces to study their tolerance to various adverse environmental stresses. the results indicated that all of these three populations could adapt to the rice variety ir26 bearing resistant gene 1 (bph1), and guangxi and yunnan populations could successfully infest rice varieties asd7 bearing bph2 and rathu heenati bearing bph3, implying that these two populations had a higher adaptab ... | 2000 | 11767535 |
| [spatial structure and pattern of nilaparvata lugens population in large-scale]. | brown planthopper(bph), nilaparvata lugens, is a major pest of rice. its spatial distribution of different generations in guangdong province was studied by using variograms. the results showed that this population distributed in a clump pattern in rice fields during the 1st rice season. 3 generations of this population had different spatial structures, with the clump range of 400 km, 200 km and 205 km respectively in the 1st rice season. the simulation distribution maps of bph, which was interpo ... | 2001 | 11757373 |
| spectral characteristics of rice plants infested by brown planthoppers. | spectral characteristics of rice plants at various levels of infestation by the brown planthopper, nilaparvata lugens (stål), (homoptera:delphacidae), in the early grain-filling stage were measured and analyzed using a spectroradiometer. plant damage was classified into six scales, i.e., 0 (ck), 1, 3, 5, 7 and 9, based on the scale of infestation displayed on the surfaces of plant parts. results showed that mean curves of reflectance spectra (350 - 1800 nm) from different scales of insect infest ... | 2001 | 11480774 |
| glutathione s-transferases as antioxidant defence agents confer pyrethroid resistance in nilaparvata lugens. | selection of a laboratory colony of the brown planthopper nilaparvata lugens with the pyrethroids permethrin and lambda-cyhalothrin increased its resistance to both insecticides. biochemical analysis and synergistic studies with metabolic inhibitors indicated that elevated glutathione s-transferases (gsts) with a predominant peroxidase activity conferred resistance to both pyrethroids, whereas esterases conferred part of the resistance to permethrin. purified esterases hydrolysed permethrin at a ... | 2001 | 11415437 |
| comparison of esterase gene amplification, gene expression and esterase activity in insecticide susceptible and resistant strains of the brown planthopper, nilaparvata lugens (stål). | organophosphorus and carbamate insecticide resistance in nilaparvata lugens is based on amplification of a carboxylesterase gene, nl-est1. an identical gene occurs in susceptible insects. quantitative real-time pcr was used to demonstrate that nl-est1 is amplified 3-7-fold in the genome of resistant compared to susceptible planthoppers. expression levels were similar to amplification levels, with 1-15-fold more nl-est1 mrna in individual insects and 5-11-fold more nl-est1 mrna in mass whole body ... | 2000 | 11122475 |
| molecular characterization of the amplified carboxylesterase gene associated with organophosphorus insecticide resistance in the brown planthopper, nilaparvata lugens. | widespread resistance to organophosphorus insecticides (ops) in nilaparvata lugens is associated with elevation of carboxylesterase activity. a cdna encoding a carboxylesterase, nl-est1, has been isolated from an op-resistant sri lankan strain of n. lugens. the full-length cdna codes for a 547-amino acid protein with high homology to other esterases/lipases. nl-est1 has an n-terminal hydrophobic signal peptide sequence of 24 amino acids which suggests that the mature protein is secreted from cel ... | 2000 | 11122474 |
| differential glycosylation produces heterogeneity in elevated esterases associated with insecticide resistance in the brown planthopper nilaparvata lugens stål. | the major insecticide resistance mechanism in the brown planthopper nilaparvata lugens involves overproduction of esterases. esterases purified from a resistant strain appeared as a ladder of bands on isoelectric focussing (ief) gels from pi 4.7 to 5.0. two-dimensional electrophoresis showed that isozymes ranged in size from 66 to 68 kda with those of lower pi being apparently smaller. all isozymes detected by two-dimensional electrophoresis were glycosylated. n-glycosidase a reduced the number ... | 2000 | 10802235 |
| actions of nitromethylenes on an alpha-bungarotoxin-sensitive neuronal nicotinic acetylcholine receptor. | nine nitromethylene analogues were tested for their actions on insect neuronal nicotinic acetylcholine receptors (nachrs). microelectrode recordings were used to study the actions of nitromethylenes on the cell body of an identified cockroach (periplaneta americana) motor neurone, the fast coxal depressor (df) in the metathoracic ganglion. six nitromethylenes showed potent nachr agonist actions; others were without nachr agonist actions. five nitromethylenes competitively displaced bound [125i]- ... | 1995 | 7566494 |
| development of monosomic alien addition lines and introgression of genes from oryza australiensis domin. to cultivated rice o. sativa l. | oryza australiensis, a diploid wild relative of cultivated rice, is an important source of resistance to brown planthopper (bph) and bacterial blight (bb). interspecific hybrids between three breeding lines of o. sativa (2n=24, aa) and four accessions of o. australiensis (2n=24, ee) were obtained through embryo rescue. the crossability ranged from 0.25% to 0.90%. the mean frequency of bivalents at diakinesis/metaphase i in f1 hybrids (ae) was 2.29 to 4.85 with a range of 0-8 bivalents. f1 hybrid ... | 1994 | 24185889 |
| molecular tagging of genes for brown planthopper resistance and earliness introgressed from oryza australiensis into cultivated rice, o. sativa. | restriction fragment length polymorphism analysis was carried out to tag the alien genes for brown planthopper (bph) resistance and earliness introgressed from wild species oryza australiensis into cultivated rice, o. sativa l. one introgression line (ir65482-4-136-2-2), resistant to biotypes 1, 2, and 3 of bph and early in flowering, was selected from bc2f4 of the cross between o. sativa (ir31917-45-3-2) and o. australiensis (accession 100882). recurrent parent, o. australiensis, and introgress ... | 1994 | 18470071 |
| diversity in steroidogenesis of symbiotic microorganisms from planthoppers. | ergosta-5,7,24(28)-trien-3β-ol (trienol)6 was isolated from the intracellular symbiotes (symbiotic microorganisms) of the planthoppers,nilaparvata lugens andlaodelphax striatellus. the steroidogenic end product of the symbiotes was found to depend on the environmental conditions, i.e., although trienol6 was produced under symbiotic conditions, ergosterol4 was formed in aerobic culture. when the normal diet was replaced by a steroiddeficient artificial one, the ratio of 24-methylenecholesterol5 t ... | 1992 | 24254785 |
| parasitism of brown planthopper and whitebacked planthopper by agamermis unka in korea. | adults of the brown planthopper (bph) and the whitebacked planthopper (wbph) that migrated into korea from china were not parasitized by the mermithid, agamermis unka. bph and wbph collected from korean rice fields were parasitized. parasitism of bph in the lst-3rd, 4th, and 5th instars, and adults was 31.5%, 61.5%, 66.4%, and 45.5%, respectively, whereas parasitism of the same stages of wbph was 50%, 50%, 100% and 90.7%, respectively. parasitism of bph by a. unka significantly reduced the numbe ... | 1990 | 19287751 |
| agamermis unka (mermithidae) parasitism of nilaparvata lugens in rice fields in korea. | the mermithid agamermis unka, a parasite of the brown planthopper (bph), was found in many rice paddies in gyeongnam province, korea. nematode parasitism of adult bph varied from year to year, reaching as high as 50% in paddies not treated with an insecticide. parasitism was lower in insecticide-treated paddies. generally, mermithid parasitism was higher in bph adults collected from the lower part (19%) compared with adults collected from the upper part (8%) of the rice plant and in brachypterou ... | 1989 | 19287605 |
| chemical association in symbiosis sterol donors in planthoppers. | the role of intracellular symbionts contributing to their host has been investigated in the planthoppers,nilaparvata lugens stal andlaodelphax striatellus fallen. we have found that the isolated yeastlike symbionts, identified as a member of the genuscandida, from the host's egg produce ergosterol when cultured. a comparative study of sterols in the cultured symbionts, the host insects, aposymbiotic host insects, and dietary plants demonstrated that ergosterol produced in the symbiotes is provid ... | 1989 | 24271450 |
| role of plant volatiles in resistance of selected rice varieties to brown planthopper,nilaparvata lugens (stål) (homoptera: delphacidae). | rice plant volatiles extracted as steam distillates significantly affected the behavior and biology of the brown planthopper,nilaparvata lugens (stål). in a multichoice test, more females settled and fed on tillers of a susceptible rice variety "taichung native 1" (tn1), sprayed with its own extract or acetone than on tn1 tillers sprayed with the extract of the resistant variety "arc6650" or "ptb33." in another test,n. lugens females ingested significantly more of a 10% sucrose solution mixed wi ... | 1985 | 24311329 |
| sensory receptors associated with the stylets and cibarium of the rice brown planthopper, nilapavarta lugens. | the stylets of nilapavarta lugens consist of two maxillae that interlock to form separate food and salivary ducts partially surrounded by two mandibles. the ultrastructure of the sensory innervation of the stylets is described. each maxilla possesses five neurones which extend to the tip of the stylet. the mandibles also contain five neurones, four of which are paired. the paired neurones comprise a shorter dendrite extending part of the way along the stylet and a longer one extending to the tip ... | 1983 | 6883435 |
| ultrastructure of sensory receptors on the labium of the rice brown planthopper. | the ultrastructure of the sensory receptors located on the labium of the rice brown planthopper is described; possible functions of individual receptors are suggested on morphological grounds. uniporous chemosensilla which may or may not possess a mechanoreceptive dendrite, domed multiporous chemosensilla, and mechanoreceptive pegs are present on the flattened labial tip. mechanoreceptive pegs are distributed over the labium. the fine structure of a multilobed sensillum located on either side of ... | 1983 | 6850772 |