| [a conbribution to the characterization of asparagus virus 2 (author's transl)]. | in host range investigations with 152 plant species of 37 families, 96 species from 28 families proved to be experimentally susceptible to asparagus virus 2 (asv 2). from these, 82 species of 26 families were systematically infectible and 14 species of 10 families only locally. most frequently were symptomless systemic infections. of 86 species, their susceptibility for asv 2 was unknown before. the number of families that contant experimental hosts of the virus increased from 11 to 33. transmis ... | 1978 | 664937 |
| engineering resistance to mixed virus infection in a commercial potato cultivar: resistance to potato virus x and potato virus y in transgenic russet burbank. | potato virus x (pvx) and potato virus y (pvy) infection in potato may result in the loss of certification of seed potatoes and affect quality and yield of potatoes in commercial production. we transformed a major commercial cultivar of potato, russet burbank, with the coat protein genes of pvx and pvy. transgenic plants that expressed both cp genes were resistant to infection by pvx and pvy by mechanical inoculation. one line was also resistant when pvy was inoculated with viruliferous green pea ... | 1990 | 1366358 |
| resistance to phloem transport of potato leafroll virus in potato plants. | a 'double-graft sandwich' technique in which sections of potato stem from different potato cultivars were grafted between a susceptible healthy stock plant and a potato leafroll virus (plrv)-infected scion was used to study the rate of phloem transport of plrv in cultivars differing in resistance to plrv infection (ir) and accumulation (ar). resistance to phloem transport (i.e. delayed plrv systemic movement) was found in bismark cultivar (ir a(s)). this was independent of ir and ar as the rate ... | 1992 | 1469360 |
| insect-mediated transmission of mixed and reassorted cucumovirus genomic rnas. | transmissions of virus using the aphid myzus persicae were performed using plants co-infected with two cucumoviruses, tomato aspermy virus (v-tav) and cucumber mosaic virus (m-cmv). five of the aphid-transmitted progeny viruses (3.7%) induced symptoms distinct from those induced by either parental virus. northern blot hybridization analysis of encapsidated rnas from these novel progeny demonstrated that all of the rna profiles were characteristic of pseudo-recombinants, i.e. viruses with reassor ... | 1992 | 1645147 |
| visualization of a luteovirus in the vector aphid's body by two gold immunolabelling techniques: a comparative study. | two gold immunolabelling techniques using electron microscopy were compared to examine the in situ localization of a luteovirus, potato leafroll virus (plrv), inside its main aphid vector, myzus persicae sulz. with gildow's technique, virus particles were labelled prior to fixation, embedding by injecting plrv-specific iggs into the living aphids. this facilitated the detection of extracellular particles located between the basal lamina and plasmalemma by trapping them in aggregates. the heavy c ... | 1991 | 1800527 |
| [a comparative study of the effect of vinyl phosphoric acid esters on cholinesterase and carboxylesterase activities in mammals and arthropods]. | studies have been made of the effect of organophosphorus inhibitors on cholinesterase and carboxylesterase from various mammals (human erythrocytes, mouse brain, blood serum of mouse and rat, blood serum of horse) and arthropods (calliphora vicina, schizaphis graminum, myzus persicae, sitophilus oryzae, pseudococcus maritimus, tetranychus urticae). organophosphorus inhibitors were presented by esters of vynylphosphoric acid containing normal and branched alkyls in the phosphoryl part of the mole ... | 1990 | 2360379 |
| coat protein of potyviruses. 4. comparison of biological properties, serological relationships, and coat protein amino acid sequences of four strains of potato virus y. | four strains of potato virus y, pvy-d, pvy-10, pvy-18, and pvy-43, obtained from different australian sources were compared on the basis of their biological, serological and coat protein structural properties. each of the strains could be distinguished on the basis of their reactions on selected test plant species. two of the pvy strains, pvy-d and pvy-10, induced symptoms similar to those produced by the pvyo strain group. the reactions of pvy-18 and pvy-43, although comparable to pvyn in some ... | 1988 | 3144263 |
| overproduction of detoxifying esterases in organophosphate-resistant culex mosquitoes and their presence in other insects. | antisera raised against the denatured polypeptide of two organophosphate-detoxifying esterases (b1 and a1) of culex mosquitoes were used in an immunoblot method to quantify esterase production in resistant versus susceptible strains and to detect the presence of immunologically related proteins in other insects. it was demonstrated that esterase b1 of culex quinquefasciatus and esterase a1 of culex pipiens are overproduced in resistant strains by factors of at least 500-fold and 70-fold, respect ... | 1987 | 3470782 |
| [the effect of salivary gland (obtained from myzus persicae sulzer) extract on broad bean epidermal cells infected with bean yellow mosaic virus (author's transl)]. | | 1974 | 4478240 |
| transmission of tobacco mosaic virus by myzus persicae. | | 1972 | 5084452 |
| aphid transmission of tobacco mosaic virus. | aphids (myzus persicae sulz.) can acquire tobacco mosaic virus from tobacco leaves coated with a virus suspension and inoculate it into healthy leaves. transmission depends on virus concentration, period of acquisition, previous feeding history of the aphids, and time between acquisition and transmission feedings. aphids whose stylets are cut do not transmit the virus. | 1969 | 5783713 |
| [some relations between the common pea mosaic virus and the peach tree aphis myzus persicae sulz]. | | 1965 | 5856645 |
| the purification of potato leafroll virus from its vector myzus persicae. | | 1967 | 6017406 |
| maximizing the detection capability of a beet western yellows virus elisa system. | conditions for maximizing detection of a california isolate of beet western yellows virus (bwyv) were investigated with the double-sandwich enzyme-linked immunosorbent assay (elisa) system. within-plate variability was found to account for less than 1% of the total variation observed on individual microtiter plates. variability across plates was greater than within plates and accounted for less than 10% of the total variation. significant reductions in absorbance were observed when either coatin ... | 1984 | 6392314 |
| changes in the amino acid sequence of the coat protein readthrough domain of potato leafroll luteovirus affect the formation of an epitope and aphid transmission. | potato leafroll luteovirus (plrv) is transmitted naturally by aphids, but two isolates (15 and v) are known to be only poorly transmissible (pat); these isolates are also distinct in that their particles lack an epitope present in transmissible (hat) isolates of plrv (tamada et al., ann. appl. biol. 104, 107-116, 1984; massalski and harrison, j. gen. virol. 68, 1813-1821, 1987). virus cultures propagated vegetatively for several years in potato plants from the source of isolate v were shown stil ... | 1994 | 7513925 |
| transmission by aphids of a naturally non-transmissible plum pox virus isolate with the aid of potato virus y helper component. | two spanish plum pox virus (ppv) isolates, 5.15 and 3.3, were used in transmission experiments involving the aphid vector myzus persicae, with woody and herbaceous host plants. these isolates differ in the size of their coat protein (cp) and sequence analysis revealed that isolate 3.3 has a 15 amino acid deletion near the n terminus of the cp, affecting the same positions as in a previously reported non-aphid-transmissible ppv isolate from germany. aphid transmission experiments showed that isol ... | 1995 | 7561767 |
| [a preliminary study on bioactivity of orange and tangerine peel extracts against aphis and mites]. | an assay was made on the bioactivity of the extracts of tangerine peel from cinocitrus tangerina, orange peel from citrus sinensis and mixed tangerine peel from cinocitrus sp. against aphis semia phis heraclei, aphis craccivora, uroleucon gobonis and myzus persicae using residual film or topical method, and against mites tetranychus viennensis and t. trancatus using slide-dip or immersion method. test results show that these extracts have strong bioactivity against aphids and mites. the correcte ... | 1995 | 7576134 |
| aphid transmission of beet western yellows luteovirus requires the minor capsid read-through protein p74. | beet western yellows luteovirus is obligately transmitted by the aphid myzus persicae in a circulative, non-propagative fashion. virus movement across the epithelial cells of the digestive tube into the hemocoel and from the hemocoel into the accessory salivary glands is believed to occur by receptor-mediated endocytosis and exocytosis. virions contain two types of protein; the major 22 kda capsid protein and the minor read-through protein, p74, which is composed of the major capsid protein fuse ... | 1995 | 7882968 |
| the peach-potato aphid myzus persicae and the tobacco aphid myzus nicotianae have the same esterase-based mechanisms of insecticide resistance. | biochemical and molecular studies have established that in the peach-potato aphid, myzus persicae, insecticide resistance is conferred by amplification of genes encoding the insecticide-detoxifying esterases e4 or fe4. here we report that two insecticide-resistant clones of the closely related tobacco aphid myzus nicotianae have elevated esterases indistinguishable from e4 and fe4 and amplified esterase dna sequences, and flanking regions, with identical restriction maps to the m. persicae genes ... | 1994 | 7894746 |
| endosymbiotic bacteria associated with circulative transmission of potato leafroll virus by myzus persicae. | in order to understand the molecular mechanisms underlying circulative transmission of potato leafroll virus (plrv) by aphids, we screened myzus persicae proteins as putative plrv binding molecules using a virus overlay assay of protein blots. in this way, we found that purified plrv particles exhibited affinity for five aphid proteins. the one most readily detected has an m(r) of 63k, and was identified as symbionin. this is the predominant protein synthesized by the bacterial endosymbiont of t ... | 1994 | 7931143 |
| cytokinin-mediated insect resistance in nicotiana plants transformed with the ipt gene. | the bacterial isopentenyl transferase (ipt) gene involved in cytokinin biosynthesis was fused with a promoter from the proteinase inhibitor ii (pi-iik) gene and introduced into nicotiana plumbaginifolia. transcripts of the ipt gene were wound-inducible in leaves of transgenic pi-ii-ipt plants. in leaf disks excised from fully expanded leaves, transcript levels increased 25- to 35-fold within 24 h and by 48 h were reduced by about 50%. in flowering plants, message levels were 2- to 5-fold higher ... | 1993 | 8219068 |
| signal for potyvirus-dependent aphid transmission of potato aucuba mosaic virus and the effect of its transfer to potato virus x. | a british isolate of potato aucuba mosaic potexvirus (pamv) was transmitted by aphids (myzus persicae) which had fed previously on a source of potato y potyvirus (pvy). nucleotide sequence analysis of the pamv coat protein gene indicated that amino acid residues 14 to 16 from the n terminus of the coat protein have the sequence dag, which is also found in the coat proteins of potyviruses and is required for their aphid transmissibility. a recombinant virus isolate (txpa7) was produced in which a ... | 1993 | 8336116 |
| the intestine is a site of passage for potato leafroll virus from the gut lumen into the haemocoel in the aphid vector, myzus persicae sulz. | four detection techniques, three of which gave reliable identification of the virus particles, were used to locate potato leafroll virus (plrv) in the alimentary canal of its main aphid vector, myzus persicae sulz: immunofluorescence on cryostat sections, conventional transmission electron microscopy on ultrathin sections and immune electron microscopy with gold labeling, either prior to or after fixation-embedding. each method clearly showed the presence of the virus in the intestine epithelium ... | 1993 | 8347080 |
| synthesis of a full-length infectious cdna clone of cucurbit aphid-borne yellows virus and its use in gene exchange experiments with structural proteins from other luteoviruses. | a full-length cdna of cucurbit aphid-borne yellows virus (cabyv) has been constructed and expressed either as an in vitro transcript, under control of a bacteriophage t7 rna polymerase promoter, or in vivo, under control of the cauliflower mosaic virus 35s promoter in an agroinfection vector. the biological activity of the cloned cdna was demonstrated by the ability of its in vitro transcript to replicate in protoplasts and of the agroinfection vector to infect agroinoculated plants. virus in th ... | 1995 | 8525610 |
| detection of potato leafroll virus in single aphids by the reverse transcription polymerase chain reaction and its potential epidemiological application. | a reverse transcription and polymerase chain reaction (rt-pcr) system was developed using two 20-mer primers located in the potato leafroll virus (plrv) capsid gene. a 336-bp pcr product was detected from aphids (myzus persicae) which had been fed on plrv-infected plants. the pcr band was specific to plrv as determined by southern blots and detection by a plrv-specific probe. as little as 5 min exposure of aphids to plrv-infected leaves resulted in the presence of plrv-specific bands in 13% of a ... | 1995 | 8576303 |
| biological and molecular properties of a pathotype p-1 and a pathotype p-4 isolate of pea seed-borne mosaic virus. | two isolates of pea seed-borne mosaic potyvirus, dpd1 and ny, were identified as pathotypes p-1 and p-4, respectively, by their infectivity on pisum sativum l. lines homozygous for the recessive resistance genes sbm-1 and sbm-4. the two isolates differed in several biological characteristics. dpd1 induced transient vein clearing, downward rolling of leaflets and internode shortening on p. sativum, whereas ny only caused a slight growth reduction. dpd1 moved systemically in chenopodium quinoa whe ... | 1996 | 8683223 |
| ultrastructural study of acquisition and retention of potato leafroll luteovirus in the alimentary canal of its aphid vector, myzus persicae sulz. | the chronology of plrv acquisition and retention by myzus persicae was investigated using electron microscopy. examination demonstrated a rapid translocation of the virus through the intestine into the haemocoel. indeed, viral particles could be observed in the intestinal epithelial cells, then in the haemocoel, 4 and 8 h, respectively, after their arrival in the lumen of the alimentary canal. however, the virus accumulated in the intestinal epithelial cells. in these cells, the first viral part ... | 1996 | 8774687 |
| detection of stylet-borne and circulative potato viruses in aphids by duplex reverse transcription polymerase chain reaction. | a reverse transcription polymerase chain reaction (rt-pcr) assay was designed to amplify stylet-borne potato virus yo (pvyo) in aphids using primers located in the viral capsid gene. a 480 bp long product was detected in aphids exposed to pvyo-infected potato plants. approximately 40% of myzus persicae and 15% of aphis nasturtii exposed briefly to pvyo-infected plants acquired the virus. this rate of acquisition by both species of aphids was typical of our earlier observation of the virus transm ... | 1996 | 8793847 |
| potyvirus transmission is not increased by pre-acquisition fasting of aphids reared on artificial diet. | aphids (myzus persicae), fasted after removal from healthy rearing plants, transmitted tobacco etch potyvirus (tev) more efficiently than unfasted aphids whether virus acquisition was from infected leaves or through membranes. there was no difference in uptake of 125i-labelled tev by fasted or unfasted aphids as measured by liquid scintillation counting. when aphids acquired 125i-labelled tev, label was retained in the stylets (as determined by autoradiographic light microscopy) by 51 % of 272 f ... | 1996 | 9000109 |
| cdna cloning, baculovirus-expression and kinetic properties of the esterase, e3, involved in organophosphorus resistance in lucilia cuprina. | resistance to organophosphorus insecticides (ops) in the sheep blowfly, lucilia cuprina, is associated with a non-staining phenotype of the carboxylesterase isozyme, e3 (e.c. 3.1.1.1). here, we show that a member of alpha-esterase multigene family, lc alpha e7, encodes e3. an lc alpha e7 cdna has been isolated from an op-susceptible strain and expressed in a baculovirus. the expressed product is the same as e3 in its electrophoretic mobility and preference for alpha-over beta-naphthyl acetate as ... | 1997 | 9061925 |
| evidence for heterologous encapsidation of potato spindle tuber viroid in particles of potato leafroll virus. | the aphid myzus persicae (sulz.) was shown to transmit potato spindle tuber viroid (pstvd) to potato clone dto-33 from source plants doubly infected with potato leafroll virus (plrv) and pstvd. transmission was of the persistent type and did not occur when the insects were allowed to feed on singly infected plants. only low levels of pstvd were associated with purified plrv virions, but its resistance to digestion with micrococcal nuclease indicates that the viroid rna is encapsidated within the ... | 1997 | 9191909 |
| potato leafroll virus binds to the equatorial domain of the aphid endosymbiotic groel homolog. | a groel homolog with a molecular mass of 60 kda, produced by the primary endosymbiotic bacterium (a buchnera sp.) of myzus persicae and released into the hemolymph, has previously been shown to be a key protein in the transmission of potato leafroll virus (plrv). like other luteoviruses and pea enation mosaic virus, plrv readily binds to extracellular buchnera groel, and in vivo interference in this interaction coincides with reduced capsid integrity and loss of infectivity. to gain more knowled ... | 1998 | 9420234 |
| amino acid changes in the coat protein of cucumber mosaic virus differentially affect transmission by the aphids myzus persicae and aphis gossypii. | cucumber mosaic virus (cmv) transmission by two aphid species was investigated using strains of the virus with modified coat proteins. chimeric viral rna 3 cdna constructs were designed with coat protein-encoding sequences from the efficiently aphid-transmitted fny-cmv and the very poorly aphid-transmitted m-cmv. different regions of the viral coat protein variably influenced transmission; the magnitude of effects depended on the aphid species used as vector. five amino acid changes in the coat ... | 1998 | 9501042 |
| role of the helper component in vector-specific transmission of potyviruses. | four aphid species were tested for their ability to transmit tobacco etch (tev) and turnip mosaic (tumv) potyviruses. myzus persicae and aphis gossypii transmitted both viruses efficiently from infected plants, whereas lipaphis erysimi transmitted only tumv and myzus ascalonicus was a poor or non-transmitter of either virus. similar electrically monitored probing patterns were produced by m. persicae, l. erysimi and m. ascalonicus, ruling out behavioural differences as the cause of differential ... | 1998 | 9634096 |
| inhibition effect of transgenic tobacco plants expressing snowdrop lectin on the population development of myzus persicae. | the cdnas of snowdrop lectin mature protein and its precursor protein, gna12 and gna34, were inserted downstream of a 35s promoter with a double enhancer and a "omega" fragment of tmv-rna cdna in the binary vector pbin438, or the phloem-specific coymv promoter in the vector pbcop1, respectively, resulting in the construction of four plant expression vectors pbgna12, pbgna34, pbcgna12, and pbcgna34. leaf stripes of nicotiana tabacum var. k326 were transformed with a. tumefaciens lba4404 harboring ... | 1998 | 9759540 |
| aphid species--vectors of plum pox virus. | plum pox virus (ppv) is widely spread by natural vectors present in plum orchards. the efficiency of transmission is dependent on the frequency of the occurrence of vectors and the cultivar susceptibility to this pathogen. having in view that ppv has a wide range of annual and multiannual host plants and vectors, there is great concern for obtaining ppv-resistant cultivars. this report deals with the following vectors: hyalopterus pruni, brachycaudus cardui, brachycaudus helichrysi. myzus persic ... | 1998 | 10073225 |
| molecular characterization and imidacloprid selectivity of nicotinic acetylcholine receptor subunits from the peach-potato aphid myzus persicae. | the recent introduction of the chloronicotinyl insecticide imidacloprid, targeting insect nicotinic acetylcholine receptors (nachrs), emphasises the importance of a detailed molecular characterisation of these receptors. we are investigating the molecular diversity of insect nachr subunit genes in an important agricultural pest, the peach-potato aphid myzus persicae. two m. persicae alpha-subunit cdnas, mp alpha1 and mp alpha2, have been cloned previously. here we report the isolation of three n ... | 1999 | 10386991 |
| a solvent-free, rapid and simple virus rna-release method for potato leafroll virus detection in aphids and plants by reverse transcription polymerase chain reaction. | a one-step, rapid and economical method for potato leafroll virus (plrv) rna release that is applicable to the use on a microcentrifuge scale is described. discs (3-6 mm diameter) from leaves, petioles, stems, and tubers of potato plants were incubated in microcentrifuge tubes with detergent solution. the supernatants were used directly for reverse transcription (rt) and polymerase chain reaction (pcr). of the seven nonionic detergents of the tritonx series evaluated, triton x405r was the most e ... | 1999 | 10598080 |
| effects of point mutations in the readthrough domain of the beet western yellows virus minor capsid protein on virus accumulation in planta and on transmission by aphids. | point mutations were introduced into or near five conserved sequence motifs of the readthrough domain of the beet western yellows virus minor capsid protein p74. the mutant virus was tested for its ability to accumulate efficiently in agroinfected plants and to be transmitted by its aphid vector, myzus persicae. the stability of the mutants in the agroinfected and aphid-infected plants was followed by sequence analysis of the progeny virus. only the mutation y201d was found to strongly inhibit v ... | 2000 | 10627524 |
| a member of the hsp60 gene family from the peach potato aphid, myzus persicae (sulzer.). | a novel cdna clone encoding a mitochondrial hsp60 was isolated from a myzus persicae cdna library. the nucleotide sequence consisted of 2348 bp and contained an open reading frame (orf) of 1722 bases. the putative protein encoded by this orf consisted of 574 amino acids and was designated mphsp60. comparison of mphsp60 with other hsp60s found that it was most similar to hsp60 from culicoides variipennis (85.6% similarity). phylogenetic analysis revealed that mphsp60 is clustered together with ot ... | 2000 | 10762429 |
| identifying the determinants in the equatorial domain of buchnera groel implicated in binding potato leafroll virus. | luteoviruses avoid degradation in the hemolymph of their aphid vector by interacting with a groel homolog from the aphid's primary endosymbiotic bacterium (buchnera sp.). mutational analysis of groel from the primary endosymbiont of myzus persicae (mpb groel) revealed that the amino acids mediating binding of potato leafroll virus (plrv; luteoviridae) are located within residues 9 to 19 and 427 to 457 of the n-terminal and c-terminal regions, respectively, of the discontinuous equatorial domain. ... | 2000 | 10775590 |
| characterization and genomic analysis of tobacco vein clearing virus, a plant pararetrovirus that is transmitted vertically and related to sequences integrated in the host genome. | a previously undescribed caulimo-like virus was identified in the hybrid tobacco species nicotiana edwardsonii, and was named tobacco vein clearing virus (tvcv) after the symptoms associated with its occurrence in this plant. the virions of tvcv are 50 nm in diameter and are composed of a 45 kda capsid protein and a 7767 bp dsdna genome. each strand of the genome is interrupted by a site-specific discontinuity. in genome sequence and arrangement of orfs tvcv was most similar to cassava vein mosa ... | 2000 | 10811941 |
| insecticidal and mutagenic evaluation of two annonaceous acetogenins. | annonaceous acetogenins represent a new class of bioactive compounds whose primary mode of action is the inhibition of nadh-ubiquinone oxidoreductase. given the potential pesticidal use of such a class of compounds, we have further evaluated the antifeedant and insecticidal effects of squamocin and annonacin, two annonaceous acetogenins, on spodoptera littoralis, leptinotarsa decemlineata, and myzus persicae. additionally, to partially assess their environmental risk, we have also tested their m ... | 2000 | 10869199 |
| host-correlated morphological variation of myzus persicae (hemiptera: aphididae) populations in greece. | morphological variation in nine characters of 157 clones of myzus persicae (sulzer) was examined by multivariate analysis. the clones were collected from peach, prunus persica, the primary host and the secondary hosts tobacco, nicotiana tabacum, cabbage, brassica oleracea, sugarbeet, beta vulgaris and pepper capsicum annuum. the 156 clones originated from various regions of greece, both in the north, where a large part of the population has an annual bisexual generation on peach, and in more sou ... | 2000 | 10996864 |
| cucumber mosaic virus mutants with altered physical properties and defective in aphid vector transmission. | two mutant strains of cucumber mosaic virus (cmv) were investigated with respect to virion stability and molecular determinants of aphid vector transmission. the mutant 2a1-mt-60x, derived from the mechanically passaged wild type 2a1-at, is poorly transmissible by the aphid aphis gossypii and not transmissible by the aphid myzus persicae, whereas the wild type virus is transmissible by both aphid species. the mutant phenotype was shown to be conferred by a single encoded amino acid change of ala ... | 2000 | 11040130 |
| lactones. 9. synthesis of terpenoid lactones-active insect antifeedants. | starting from (+)- and (-)-perillyl alcohols, via claisen rearrangement and iodolactonization, four enantiomeric pairs of gamma-lactones were obtained. the structures of compounds were established by both spectroscopic and crystallographic methods. the lactones were tested for antifeeding activity toward grain storage pests-the granary weevil beetle (sitophilus granarius l.), the khapra beetle (trogoderma granarium ev.), and the confused flour beetle (tribolium confusum duv.). the results of the ... | 2000 | 11052764 |
| the passage of potato leafroll virus through myzus persicae gut membrane regulates transmission efficiency. | potato leafroll virus (plrv) is transmitted by aphids in a persistent manner. although virus circulation within the aphid leading to transmission has been well characterized, the mechanisms involved in virus recognition at aphid membranes are still poorly understood. one isolate in our collection (plrv-14.2) has been shown to be non- or only poorly transmitted by some clones of aphids belonging to the myzus persicae complex. to determine where the transmission process was blocked within the aphi ... | 2001 | 11125153 |
| some epidemiological approaches to the control of aphid-borne virus diseases in seed potato crops in northern europe. | an account is given of progress during the last 30 years in knowledge of the epidemiology of diseases caused by aphid-borne viruses in seed potato production areas of northern europe. during this period, potato leafroll virus (plrv) and strains of potato virus y (pvy(o), pvy(n)) were consistently the most prevalent and harmful. the main factors influencing spread involve the amount of initial virus inoculum in seed crops, agricultural practices in relation to seed potato production, the status o ... | 2000 | 11137160 |
| extreme resistance to potato leafroll virus in potato cv. russet burbank mediated by the viral replicase gene. | high levels of field resistance to potato leafroll virus (plrv; genus: polerovirus; family: luteoviridae) were achieved by expression of the unmodified, full-length plrv replicase gene in potato plants cv. russet burbank. a high degree of resistance was also achieved, but less frequently, by expression of a truncated construct of the replicase gene. in limited testing, neither miss-frame nor antisense constructs of the replicase gene conferred resistance. the degree of resistance expressed among ... | 2000 | 11137161 |
| differentiation of celosia mosaic virus and asparagus virus 1 based on biological properties. | an attempt was made to distinguish between celosia mosaic virus (cimv) and asparagus virus 1 (av-1) based on biological properties, which hitherto was obscured from serological data from previous work. the host range of av-1 was found to be a subset of that of cimv and av-1 was transmitted by the aphid myzus persicae which, on the other hand, did not transmit cimv. no evidence of cross-protection was obtained between these two viruses. | 2000 | 11155362 |
| [3h]-methyllycaconitine: a high affinity radioligand that labels invertebrate nicotinic acetylcholine receptors. | nicotinic acetylcholine receptors (nachr) of insect and other invertebrates are heterogeneous and new tools are needed to dissect their multiplicity. [(3)h]-methyllycaconitine ([(3)h]-mla) is a novel radioligand which is a potent antagonist at vertebrate alpha7-type nachr. putative invertebrate nachr of the aphid myzus persicae, the moths heliothis virescens and manduca sexta, the fly lucilia sericata, and the squid loligo vulgaris were investigated in radioligand binding studies with [(3)h]-mla ... | 2001 | 11267892 |
| modified atmosphere treatments as a potential disinfestation technique for arthropod pests in greenhouses. | incidental transport of arthropods on plant material can be a significant mode of pest entry into greenhouses. we evaluated the use of controlled atmosphere treatments as a potential way to eliminate arthropod pests on plant propagules (i.e., cuttings or small rooted plants). lethal exposures to co2 or n2 were determined for common greenhouse pests including fungus gnat larvae, bradysia sp.; green peach aphid, myzus persicae (sulzer); sweetpotato whitefly, bemisia sp.; twospotted spider mite, te ... | 2001 | 11332835 |
| studies on the role of the minor capsid protein in transport of beet western yellows virus through myzus persicae. | beet western yellows virus (bwyv), family luteoviridae, is an icosahedral plant virus which is strictly transmitted by aphids in a persistent and circulative manner. virions cross two cellular barriers in the aphid by receptor-based mechanisms involving endocytosis and exocytosis. particles are first transported across intestinal cells into the haemolymph and then across accessory salivary gland cells for delivery to the plant via saliva. we identified the midgut part of the digestive tract as t ... | 2001 | 11458007 |
| population-scale laboratory studies of the effect of transgenic plants on nontarget insects. | studies of the effects of insect-resistant transgenic plants on beneficial insects have, to date, concentrated mainly on either small-scale "worst case scenario" laboratory experiments or on field trials. we present a laboratory method using large population cages that represent an intermediate experimental scale, allowing the study of ecological and behavioural interactions between transgenic plants, pests and their natural enemies under more controlled conditions than is possible in the field. ... | 2001 | 11472551 |
| microsatellite isolation, linkage group identification and determination of recombination frequency in the peach-potato aphid, myzus persicae (sulzer) (hemiptera: aphididae). | fifteen polymorphic microsatellite markers were used to establish linkage groups and relative rates of recombination in male and female myzus persicae (sulzer) (hemiptera: aphididae) (peach-potato aphid). we cloned nine markers from m. persicae and for these we report primer sequences and levels of allelic diversity and heterozygosity in four australian m. persicae populations. of the remaining six loci, four loci, also cloned from m. persicae, were obtained from g. malarky (natural history muse ... | 2001 | 11486508 |
| [studies on transgenic tobacco plants expressing two kinds of insect resistant genes]. | a synthetic bt cry1ac gene fussed with a secretary signal coding sequences at 5' end and a modified gna gene were used to construct a plant expression vector pbsgs1m+ and this vector was transferred into tobacco (nicotiana tabacum l.) by agrobacterium-mediated transformation method. results of pcr, southern blot and slot blot analysis indicated that both the chimeric bt cry1ac and gna genes were integrated into the genomes of transformed plants. western blot analysis indicated that at least the ... | 2001 | 11517599 |
| how species-specific is the phoretic relationship between the broad mite, polyphagotarsonemus latus (acari: tarsonemidae), and its insect hosts? | broad mite, polyphagotarsonemus latus (acari: tarsonemidae), is a serious plant pest in tropical and subtropical regions. phoretic associations between broad mite and two genera of whiteflies (insecta: homoptera: aleyrodidae). namely bemisia and trialeurodes, have been reported from different parts of the world. our purpose was to determine the specificity of the association between the mite and its phoretic hosts. two host plants, potatoes and cucumbers, were used to study these relationships i ... | 2001 | 11523917 |
| green peach aphid (homoptera: aphididae) action thresholds for controlling the spread of potato leafroll virus in idaho. | arbitrary green peach aphid, myzus persicae (sulzer), action thresholds (0, 5, 10, 20, and 40 aphids per 100 leaves) were tested in 3 yr of field experimentation to determine if they could be maintained and if they would significantly impact aphid densities and limit the incidence of potato leafroll virus (plrv). in 1997 and 1998, significant linear relationships between thresholds and final percentage of plrv (expressed as the percentage of tubers infected with plrv) were observed: there was a ... | 2001 | 11777033 |
| volatiles from potato plants infected with potato leafroll virus attract and arrest the virus vector, myzus persicae (homoptera: aphididae). | the influence of viral disease symptoms on the behaviour of virus vectors has implications for disease epidemiology. here we show that previously reported preferential colonization of potatoes infected by potato leafroll virus (genus polerovirus) (luteovirus) (plrv) by alatae of myzus persicae, the principal aphid vector of plrv, is influenced by volatile emissions from plrv-infected plants. first, in our bioassays both differential immigration and emigration were involved in preferential coloni ... | 2002 | 11886636 |
| microsatellite variation in cyclically parthenogenetic populations of myzus persicae in south-eastern australia. | we examined the population structure of the introduced aphid, myzus persicae collected mainly from its primary host, prunus persica, in south-east australia. myzus persicae has been present in australia since at least 1893. samples were collected in the spring of 1998 from two mainland and three tasmanian localities and isofemale lines were established in the laboratory. the reproductive mode (life cycle), karyotype and 17-locus microsatellite genotype of each clone were determined. all populati ... | 2002 | 11920132 |
| fluorometric microplate assay to measure glutathione s-transferase activity in insects and mites using monochlorobimane. | elevated levels of glutathione s-transferases (gsts) play a major role as a mechanism of resistance to insecticides and acaricides in resistant pest insects and mites, respectively. such compounds are either detoxicated directly via phase i metabolism or detoxicated by phase ii metabolism of metabolites as formed by microsomal monooxygenases. here we used monochlorobimane (mcb) as an artificial substrate and glutathione to determine total gst activity in equivalents of single pest insects and sp ... | 2002 | 11950219 |
| transgenic potatoes with enhanced levels of nematode resistance do not have altered susceptibility to nontarget aphids. | cysteine proteinase inhibitors (cystatins) confer resistance to plant-parasitic nematodes when expressed in transgenic plants. the survival and growth of nymphs of the peach-potato aphid, myzus persicae, were adversely affected when cystatins were added to artificial diets. when aphids were clip-caged onto transgenic plants expressing chicken egg white cystatin (cewc) there was no adverse effect on aphid fitness. field populations of aphids on transgenic desiree potatoes, expressing cewc or a mo ... | 2002 | 11972767 |
| effect of cabbage cultivars with varying levels of resistance to aphids on the performance of the parasitoid, aphidius colemani (hymenoptera: braconidae). | the effect of aphid resistance in plant cultivars on parasitism of myzus persicae (sulzer) and brevicoryne brassicae (linnaeus) by aphidius colemani viereck was investigated under laboratory conditions using three cultivars of common cabbage, brassica oleracea var. capitata. significantly greater aphid populations were found on cv. derby day (green-leaved, susceptible to both aphid species), regardless of the presence or absence of parasitoids, compared with cv. minicole (green-leaved, partially ... | 2002 | 12020362 |
| variation in the life cycle and morphology of the tobacco host-race of myzus persicae (hemiptera: aphididae) in relation to its geographical distribution. | morphological variation and life cycle category were examined in 121 clones of myzus persicae (sulzer). the clones were collected from tobacco from three localities in greece (xanthi, nea efessos and naphplion), one in germany (rheinstetten), one in france (bergerac) and one in spain (madrid). before morphometrics, all aphids were laboratory-reared on potato. the morphological variation was investigated using both canonical variates analysis and a novel non-parametric classification tree method. ... | 2002 | 12191438 |
| life cycle variation of myzus persicae (hemiptera: aphididae) in greece. | during the years 1995-1999 the life cycle category of 2797 clones of myzus persicae (sulzer) was examined. the clones originated from primary and secondary hosts from different localities of north and central greece and the island of crete in the south. four different overwintering life cycle strategies were found that have also been described for m. persicae and other heteroecious species previously. a geographical variation was found in the proportion of holocyclic clones from tobacco and othe ... | 2002 | 12191439 |
| [time-specific infection rate of beauveria bassiana on myzus persicae after topical inoculation of conidial suspension]. | conidial suspension(5 x 10(6) conidia.ml-1) of the entomopathogenic fungus, beauveria bassiana bbsg8702 was used to inoculate newly emerged apterous adults of the green peach aphid (myzus persicae) on detached cabbage leaves in order to measure time-specific infection rate of the fungal agent. the aphids of conidia attached were disinfected using 0.2% chlorothalonil solution at intervals of 8-56 h after inoculation and then maintained at 10 and 20 degrees c for daily observation. there was a sig ... | 2002 | 12216397 |
| analysis of insecticide-resistant myzus persicae (sulzer) populations collected in italian peach orchards. | several populations of the green peach aphid, myzus persicae (sulzer), were collected in the most important italian peach-growing areas. in these populations, collected as primary colonies or as secondary ones, total esterase content and acetylcholinesterase sensitivity towards pirimicarb was assessed using biochemical assays. most of the individuals analysed generally exhibited an elevated esterase content, and in some cases acetylcholinesterase insensitivity. the implications of resistance lev ... | 2002 | 12233192 |
| constitutive activation of jasmonate signaling in an arabidopsis mutant correlates with enhanced resistance to erysiphe cichoracearum, pseudomonas syringae, and myzus persicae. | in arabidopsis spp., the jasmonate (ja) response pathway generally is required for defenses against necrotrophic pathogens and chewing insects, while the salicylic acid (sa) response pathway is generally required for specific, resistance (r) gene-mediated defenses against both biotrophic and necrotrophic pathogens. for example, sa-dependent defenses are required for resistance to the biotrophic fungal pathogen erysiphe cichoracearum ucsc1 and the bacterial pathogen pseudomonas syringae pv. macul ... | 2002 | 12437300 |
| a new virus infecting myzus persicae has a genome organization similar to the species of the genus densovirus. | the genomic sequence of a new icosahedral dna virus infecting myzus persicae has been determined. analysis of 5499 nt of the viral genome revealed five open reading frames (orfs) evenly distributed in the 5' half of both dna strands. three orfs (orf1-3) share the same strand, while two other orfs (orf4 and orf5) are detected in the complementary sequence. the overall genomic organization is similar to that of species from the genus densovirus: orfs 1-3 most likely encode the non-structural prote ... | 2003 | 12533713 |
| [biomass, sporulation and aphid-infecting virulence of pandora neoaphidis mycelia produced in repeated liquid culture]. | repeated culture of entomophthoraceous isolates is a suspectable factor leading to their virulence decline of biological variation. in the present study, an isolate of pandora neoaphidis, f98028, was repeatedly cultured six times at the regime of 20 degrees c and 80 r/min in sabouraud dextrose broth(sdb) at three inoculation ratio of 1/20, 2/20, and 4/20 (seed culture over fresh sdb). mycelial biomass(mb), sporulation capacity(sc), and virulence to the green peach aphid, myzus persicae, were ass ... | 2001 | 12549095 |
| selection by phage display of a variant mustard trypsin inhibitor toxic against aphids. | the mustard trypsin inhibitor, mti-2, is a potent inhibitor of trypsin with no activity towards chymotrypsin. mti-2 is toxic for lepidopteran insects, but has low activity against aphids. in an attempt to improve the activity of the inhibitor towards aphids, a library of inhibitor variants was constructed and cloned into the prlac3 phagemid vector. the library of 9.3 x 107 independent colonies was created by randomisation of a stretch of five consecutive codons in the reactive site. repeated sel ... | 2003 | 12581313 |
| laboratory evaluation of temperature effects on the germination and growth of entomopathogenic fungi and on their pathogenicity to two aphid species. | as part of an approach to select potential mycoinsecticides for aphid biocontrol, we investigated the effects of temperature on the growth, germination and pathogenicity of some hyphomycete fungi. commercially available mycoinsecticides (based on beauveria bassiana (balsamo) vuillemin and verticillium lecanii (zimmermann) viegas) and other isolates of b bassiana, v lecanii, metarhizium anisopliae (metschnikoff) sorokin and paecilomyces fumosoroseus (wize) brown & smith were evaluated. the rate o ... | 2003 | 12587869 |
| biological characteristics of the mirids macrolophus costalis and macrolophus pygmaeus preying on the tobacco form of myzus persicae (hemiptera: aphididae). | biological and population parameters of the predatory bugs macrolophus costalis fieber and macrolophus pygmaeus rambur preying on the tobacco aphid myzus persicae (sulzer) were examined. tobacco was used as host plant and all experiments were carried out at 23 degrees c and l16:d8. in m. costalis, the developmental time for eggs and the total duration of nymphal instars was 13.1 and 22.2 days and in m. pygmaeus 13.0 and 20.2 days, respectively. both species completed their nymphal development fe ... | 2003 | 12593681 |
| [role of contagious infection of pandora delphacis in suppression of myzus persicae colonies]. | the colonies of green peach aphid, myzus persicae, on detached cabbage leaves (8 replicates) were initiated with each including 3 apterae exposed to 'spore shower' of the entomophthoraceous fungus, pandora delphacis, to evaluate its potential for aphid control. the colonies were then allowed to freely propagate and infect from one to another for mycosis development at different regimes of temperature (10-30 degrees c) and relative humidity (74-100% rh). during a period of 30-day observation, aph ... | 2002 | 12625001 |
| co-existence of different host-adapted forms of the myzus persicae group (hemiptera: aphididae) in southern italy. | multivariate morphometric analysis (method of canonical variates) was used to compare 38 parthenogenetic lineages and three field collections of aphids of the myzus persicae (sulzer) group sampled on peach and tobacco in the caserta region of southern italy. comparisons were also made with the morphology of lineages collected on peach in lehonia, in central eastern greece away from tobacco-growing regions, and on tobacco in naphplion, in southern greece. the lineages were measured after partheno ... | 2003 | 12699534 |
| tritrophic interactions between transgenic potato expressing snowdrop lectin (gna), an aphid pest (peach-potato aphid; myzus persicae (sulz.) and a beneficial predator (2-spot ladybird; adalia bipunctata l.). | tritrophic interactions between transgenic potato expressing the insecticidal lectin from snowdrop (galanthus nivalis agglutinin; gna), an aphid pest, myzus persicae (sulz.), and a beneficial predator, the 2-spot ladybird (adalia bipunctata l.) were investigated. clonal plants expressing gna at 0.1-0.2% total soluble protein in leaves were used. no significant effects on development and survival of ladybird larvae fed on aphids from these transgenic plants were observed, with larval survival in ... | 2003 | 12739890 |
| performance of myzus persicae (hemiptera: aphididae) clones on different host-plants and their host preference. | the performance of eighteen clones of myzus persicae (sulzer) on pepper and tobacco plants at 20 degrees c and l16:d8 and the choice of young adult apterae between tobacco and pepper leaf-discs were examined. the clones were collected from weeds and peach in two tobacco-growing regions: katerini, northern greece and karditsa, central greece (only from weeds) and from lehonia, central eastern greece where tobacco is not cultivated. all clones did well on both hosts. however, the analysis of data ... | 2003 | 12762865 |
| effects of artificial diet containing gna and gna-expressing potatoes on the development of the aphid parasitoid aphidius ervi haliday (hymenoptera: aphidiidae). | aphid parasitoids are important biological control agents. the possibility arises that whilst foraging on insect-resistant transgenic plants, they are themselves at risk from direct and indirect effects of the expression of a transgene used to control the pest species. a liquid artificial diet was successfully used to deliver the snowdrop lectin (galanthus nivalis agglutinin; gna) to the peach-potato aphid, myzus persicae. bioassays utilising artificial diet incorporating gna, and excised leaves ... | 2001 | 12770142 |
| snowdrop lectin (gna) has no acute toxic effects on a beneficial insect predator, the 2-spot ladybird (adalia bipunctata l.). | two-spot ladybird (adalia bipunctata l.) larvae were fed on aphids (myzus persicae (sulz.)) which had been loaded with snowdrop lectin (galanthus nivalis agglutinin; gna) by feeding on artificial diet containing the protein. treatment with gna significantly decreased the growth of aphids. no acute toxicity of gna-containing aphids towards the ladybird larvae was observed, although there were small effects on development. when fed a fixed number of aphids, larvae exposed to gna spent longer in th ... | 2000 | 12770202 |
| effects of earthworms and organic litter distribution on plant performance and aphid reproduction. | human management practices and large detritivores such as earthworms incorporate plant litter into the soil, thereby forming a heterogeneous soil environment from which plant roots extract nutrients. in a greenhouse experiment we investigated effects of earthworms and spatial distribution of (15)n-labelled grass litter on plants of different functional groups [ lolium perenne (grass), plantago lanceolata (forb), trifolium repens (legume)]. earthworms enhanced shoot and root growth in l. perenne ... | 2003 | 12844255 |
| spatial and temporal genetic variability in french populations of the peach-potato aphid, myzus persicae. | the peach-potato aphid, myzus persicae (sulzer), has a complex reproductive mode in which some lineages reproduce by continuous parthenogenesis, whereas others reproduce sexually once a year. the climate is thought to act directly on the reproductive mode, because sexual eggs are the only form that can resist frost in cold regions. sexual reproduction necessitates an obligatory host alternation that may result in long-distance dispersal. here, we examined the genetic variability at seven microsa ... | 2003 | 12886281 |
| incidence of insecticide resistance alleles in sexually-reproducing populations of the peach-potato aphid myzus persicae (hemiptera: aphididae) from southern france. | intensive chemical treatments have led to the development of a number of insecticide resistance mechanisms in the peach-potato aphid myzus persicae (sulzer). some of these mechanisms are known to be associated with negative pleiotropic effects (resistance costs). molecular and biochemical methods were used to determine the genotypes or phenotypes associated with four insecticide resistance mechanisms in single aphids from sexually-reproducing populations in southern france. the mechanisms consid ... | 2003 | 12908914 |
| [field efficacy of emulsifiable suspensions of beauveria bassiana conidia for control of myzus persicae population on cabbage]. | the conidial powder of beauveria bassiana sg8702 produced using a diphasic fermentation technology was formulated into emulsifiable suspension i (ei-i, > 10(10) conidia.ml-1) and es-ii, which resulted from adding 1% (w/v) of imidacloprid 10% wp to the es-i. three dilutions (10(7), 10(6), and 10(5) conidia.ml-1 of each were sprayed onto cabbage plants for control of the green peach aphid myzus persicae population in field plots in kunming, yunnan during july 2001. each dilution and a water spray ... | 2003 | 12920898 |
| the green peach aphid on tobacco in the dominican republic. | | 1952 | 13028257 |
| evidence that potato virus y is carried near the tip of the stylets of the aphid vector myzus persicae (sulz.). | | 1955 | 13270154 |
| does the aphid myzus persicae (sulz.) imbibe tobacco mosaic virus? | | 1956 | 13325405 |
| new use of broomcorn millets for production of granular cultures of aphid-pathogenic fungus pandora neoaphidis for high sporulation potential and infectivity to myzus persicae. | glutinous broomcorn millets from the crop panicum miliaceum were first used as substrate to produce granular cultures of pandora neoaphidis, an obligate fungal pathogen specific to aphids. carrying a water content of 36.5% after being steamed in a regular autoclaving procedure, millet grains of each 15 g (dry weight) in a 100-ml flask were mixed with 3 ml modified sabouraud dextrose broth containing half a mashed colony of p. neoaphidis grown on egg yolk milk agar and then incubated at 20 degree ... | 2003 | 14592724 |
| dose-response relationship in lethal and behavioural effects of different insecticides on the parasitic wasp aphidius ervi. | neurotoxic insecticides are widely used for crop protection and behavioural perturbations can be expected in surviving beneficial insects, including parasitoids of pest insects. the present study aims to investigate the relationship between the dose of insecticide parasitoids have been exposed to, and the subsequent ability of these parasitoids to respond to host-related cues. a four-armed olfactometer, a design widely used to observe orientation responses in various insects and parasitoids in p ... | 2004 | 14599507 |
| transformation of tobacco with genes encoding helianthus tuberosus agglutinin (hta) confers resistance to peach-potato aphid (myzus persicae). | the effects of the hta gene encoding helianthus tuberosus agglutinin (hta) on an insect in the order homoptera were investigated. homologous cdnas of hta-a, hta-b, hta-c and hta-d with camv35s as promoter were introduced into tobacco via agrobacterium tumefaciens. southern blot results showed that the exogenous hta gene was inserted into the genome of host plants, and northern blot analysis confirmed that hta was expressed in transgenic plants. a bioassay with peach-potato aphid (myzus persicae) ... | 2003 | 14601659 |
| association of mace-based insecticide resistance in myzus persicae with reproductive rate, response to alarm pheromone and vulnerability to attack by aphidius colemani. | reproductive success and response to alarm pheromone, both potentially important components of fitness, were assessed using clones of myzus persicae (sulzer) to establish associations with insecticide resistance conferred by insensitive modified acetylcholinesterase (mace). both traits showed significant trends that were apparently related to this mechanism. mace forms appeared to reproduce at slower rates than non-mace forms expressing moderate (r1) levels of another resistance mechanism based ... | 2003 | 14620042 |
| probiotic effects of beta-glucuronidase on the peach-potato aphid myzus persicae (aphididae). | beta-glucuronidase (gus) is a reporter protein commonly expressed in transgenic plants allowing the visualization of the transformed individuals. in our recent work, we showed that consumption of transformed potato plants expressing this gus enzyme improves performance of the phloem feeding aphid myzus persicae. those results led us to the conclusion that the expression of gus in potato plants might be responsible for the probiotic effect measured in feeding aphids. in the present paper, artific ... | 2003 | 14624892 |
| environmentally related patterns of reproductive modes in the aphid myzus persicae and the predominance of two 'superclones' in victoria, australia. | asexual organisms that naturally coexist with sexual relatives may hold the key to understanding the maintenance of sex and recombination, a long-standing problem in evolutionary biology. this situation applies to the peach-potato aphid, myzus persicae, in southeastern australia where cyclical parthenogens form mixed populations with obligate parthenogens. we collected m. persicae from several areas across victoria, genotyped them at seven microsatellite loci and experimentally determined their ... | 2003 | 14629364 |
| posterior midgut and hindgut are both sites of acquisition of cucurbit aphid-borne yellows virus in myzus persicae and aphis gossypii. | members of the family luteoviridae ('luteovirids') rely strictly on aphid vectors for plant-to-plant transmission. this interaction operates according to a persistent and circulative manner, which implies that the virions are being endocytosed and exocytosed across two epithelial barriers (alimentary tract and accessory salivary glands) in the vector's body. in several luteovirid-aphid vector species combinations, the route of virions in the insect has been investigated ultrastructurally by tran ... | 2003 | 14645929 |
| changes in genotypic composition of myzus persicae (hemiptera: aphididae) on tobacco during the past two decades in japan. | ninety-nine and 476 clones of myzus persicae (sulzer) were sampled on tobacco at kyoto (shimogamo) (1996-2000) and at 23 other localities (1998-1999) in japan, respectively. the clones were classified into colour-esterase forms, distinguished by combinations of body colour and electrophoretically detectable esterases, to verify the changes in genotypic composition during the past two decades. fifteen and 31 colour-esterase forms were found at kyoto (shimogamo) and at 23 other localities, respect ... | 2003 | 14704100 |
| transgenic tobacco expressing pinellia ternata agglutinin confers enhanced resistance to aphids. | tobacco leaf discs were transformed with a plasmid, pbipta, containing the selectable marker neomycin phosphotransferase gene (nptii) and pinellia ternata agglutinin gene (pta) via agrobacterium tumefaciens-mediated transformation. thirty-two independent transgenic tobacco plants were regenerated. pcr and southern blot analyses confirmed that the pta gene had integrated into the plant genome and northern blot analysis revealed transgene expression at various levels in transgenic plants. genetic ... | 2003 | 14713200 |
| expression of functionally active helper component protein of tobacco etch potyvirus in the yeast pichia pastoris. | tobacco etch potyvirus (tev) is transmitted by aphids in a non-persistent manner with the assistance of a virus-encoded protein known as helper component (hc-pro). to produce a biologically active form of recombinant tev hc-pro protein, heterologous expression in the methylotrophic yeast pichia pastoris was used. a cdna encoding the tev hc-pro region, fused to a saccharomyces cerevisiae alpha-mating factor secretory peptide coding region, was inserted into the p. pastoris genome using a modified ... | 2004 | 14718639 |
| further characterization of 'sweet potato virus 2': a distinct species of the genus potyvirus. | an incompletely described potyvirus isolate from sweet potato in taiwan, referred to as 'sweet potato virus 2' (spv2), was further characterised. electron microscopy revealed that spv2 has filamentous particles of 850 nm in length and induces cytoplasmic cylindrical inclusions consisting of pinwheels and scrolls. the virus was mechanically transmitted to several species of the genera chenopodium, datura, nicotiana, and ipomoea. two biotypes of myzus persicae transmitted spv2 in a non-persistent ... | 2004 | 14745592 |
| genetic diversity and insecticide resistance of myzus persicae (hemiptera: aphididae) populations from tobacco in chile: evidence for the existence of a single predominant clone. | the tobacco-feeding race of myzus persicae (sulzer), formerly known as m. nicotianae blackman, was introduced into chile during the last decade. in order to evaluate the genetic diversity and insecticide resistance status of chilean tobacco aphid populations, a field survey was conducted in 35 tobacco fields covering a 300 km latitudinal survey. the populations sampled were characterized using microsatellite markers and morphometric multivariate analysis. insecticide resistance levels were asses ... | 2004 | 14972045 |
| mode of inheritance of the polymorphic esterases in myzus persicae (hemiptera: aphididae) in japan. | crossing experiments were conducted with 43 different parental clones of myzus persicae (sulzer) to clarify the genetic bases of esterase variations detected by electrophoresis. a total of 468 f1 clones obtained were analysed for variants at six polymorphic esterase loci, including one associated with resistance to organophosphorus insecticides (rae). in addition, the effect of six different host plants on the activity of esterases was examined. the inheritance of variants at two loci could be e ... | 2004 | 14972051 |
| activity of aphids associated with lettuce and broccoli in spain and their efficiency as vectors of lettuce mosaic virus. | this research sought to identify the aphid virus vector species associated with lettuce and broccoli crops in spain, and to determine their population dynamics and ability to transmit lettuce mosaic virus (lmv). green tile traps and moericke yellow water-pan traps were used to monitor aphid flights during the spring and autumn growing seasons of 2001. aphid species feeding on lettuce were counted weekly. the transmission efficiencies of lmv were determined for the aphid species caught most frequ ... | 2004 | 15036838 |