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1.
Plant Dis ; 108(2): 291-295, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37755419

RESUMO

Tomato (Solanum lycopersicum L., family Solanaceae) represents one of the most economically valuable horticultural crops worldwide. Tomato production is affected by numerous emerging plant viruses. We identified, for the first time in New Zealand (NZ), Pepino mosaic virus (PepMV) in greenhouse grown tomato crops using a combination of methods from electron microscopy and herbaceous indexing to RT-qPCR and high-throughput sequencing. Phylogenetic and genomic analysis of a near-complete PepMV genome determined that the detected strain belonged to the mild form of the CH2 lineage of the virus. Subsequently, a delimiting survey of PepMV was conducted, and PepMV was detected at four additional locations. PCR-derived sequences obtained from samples collected from different greenhouses and from herbaceous indicator plants were identical to the original sequence. Since PepMV has never been reported in NZ before, seed pathways are speculated to be the most likely source of entry into the country.


Assuntos
Potexvirus , Solanum lycopersicum , Filogenia , Nova Zelândia , Doenças das Plantas
2.
Plant Dis ; 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488982

RESUMO

Fig (Ficus carica) has been cultivated since ancient times, and is now grown worldwide, both for its fruit and as an ornamental plant. Several viruses and viroids are associated with Fig mosaic disease (FMD), a disease complex occurring worldwide (Preising et al. 2021). Fig mosaic virus (FMV), fig leaf mottle-associated virus 1 (FLMaV-1), fig mild mottle-associated virus (FMMaV), and fig badnavirus 1 (FBV-1) are known to infect fig in New Zealand (Minafra et al. 2012; Veerakone et al. 2015). In December 2020, leaf samples from a fig tree growing on the roadside at St Heliers, Auckland, showing dieback with foliar chlorotic mosaic symptoms, was received for virus testing. Total nucleic acid was extracted from the symptomatic leaves using a KingFisher™ mL Purification System (Thermofisher Scientific, Waltham, MA) with an InviMag Plant DNA Mini Kit (Invitek Molecular GmbH, Germany) and subjected to high-throughput sequencing on an Oxford Nanopore Technologies MinION device using the method described in Liefting et al. 2021. All sequence analysis was performed using Geneious Prime 2021.1.1 (https://www.geneious.com). A total of 355,858 reads that passed quality check were subjected to BLASTn search against the NCBI nt database as described in Liefting et al. 2021. The following viruses produced hits: FMV, FBV-1, FMMaV and a fig closterovirus. The presence of FMV, FBV-1 and FMMaV were confirmed by species specific RT-PCRs. To identify the closterovirus, reads were mapped to closteroviruses reported in fig including the recently identified tentative species fig virus A (FiVA; GenBank accession no MN817232) and fig virus B (FiVB; GenBank accession no. MN817233). Five viral contigs ranging from 939 to 2,340 nucleotides (nt) were obtained from mapping to FiVB. Subsequently, a 6.4 kb sequence (GenBank accession no. OQ968551) from the 3' region of the NZ isolate was amplified by overlapping RT-PCR using primers designed from the contig sequences. The sequence shared 79.5% nucleotide (nt) identity with FiVB The original sample and a further 25 symptomatic and 10 asymptomatic fig samples, collected from the Auckland area between 2016 and 2021, were tested using FiVB specific RT-PCR and Sanger sequencing using primers FiVB-F1 (5'-GAGGGAGAGATGTAGATGC-3') and FiVB-R2 (5'-TGTCGTCGATATCGTTGTGT-3'), designed to amplify a 725 nt fragment in the 70 kDa heat shock protein (HSP70) ORF. Products of the expected size were amplified from the original sample and three symptomatic samples and their sequences found to be identical. BLAST searches showed that the sequence (GenBank accession no. ON553403) shared 82.7% nt and 87.3% amino acid (aa) identity to an isolate of FiVB (GenBank accession no MN817233). These additional positive samples were collected from a small home nursery where the plants were propagated from cuttings and have been distributed locally, suggesting the virus is very likely to have a limited spread throughout the Auckland area. All three FiVB infected samples were also positive for FMV. However, the association of FiVB with FMD symptoms is unknown. FiVB was first identified from a latex sample exuded from a fig tree collected from Japan (Park et al. 2021) and is the only report of FiVB in the world to date. Although an identical sequence from Argentina, named fig closterovirus 1, was submitted to GenBank, the origin of this isolate is not known. To our knowledge, this is the first report of FiVB in New Zealand.

3.
J Health Commun ; 27(5): 292-301, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35866549

RESUMO

This experiment examined how two language features-linguistic agency and assignment of causality-of online support-seekers' messages regarding depression influenced viewers' perceived stigma and features of their support messages. Participants (N = 254) read and responded to an online support-seeking post about depression. Our results revealed that personal stigma toward a depressed individual was lower when the individual disclosed a biological cause for the depression and assigned agency to depression than agency to human. Additionally, when agency was assigned to depression with a biological rather than non-biological cause, more positive emotion words were utilized in participants' response posts. Cognitive process words were used more often in response to messages with non-biological causality than biological causality.


Assuntos
Depressão , Estigma Social , Depressão/psicologia , Humanos , Idioma , Linguística , Percepção Social
4.
Front Plant Sci ; 13: 878733, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35665190

RESUMO

Certain viruses dramatically affect yield and quality of potatoes and have proved difficult to eradicate with current approaches. Here, we describe a reliable and efficient virus eradication method that is high throughput and more efficacious at producing virus-free potato plants than current reported methods. Thermotherapy, chemotherapy, and cryotherapy treatments were tested alone and in combination for ability to eradicate single and mixed Potato virus S (PVS), Potato virus A (PVA), and Potato virus M (PVM) infections from three potato cultivars. Chemotherapy treatments were undertaken on in vitro shoot segments for four weeks in culture medium supplemented with 100 mg L-1 ribavirin. Thermotherapy on in vitro shoot segments was applied for two weeks at 40°C (day) and 28°C (night) with a 16 h photoperiod. Plant vitrification solution 2 (PVS2) and cryotherapy treatments included a shoot tip preculture followed by exposure to PVS2 either without or with liquid nitrogen (LN, cryotherapy) treatment. The virus status of control and recovered plants following therapies was assessed in post-regeneration culture after 3 months and then retested in plants after they had been growing in a greenhouse for a further 3 months. Microtuber production was investigated using in vitro virus-free and virus-infected segments. We found that thermotherapy and cryotherapy (60 min PVS2 + LN) used alone were not effective in virus eradication, while chemotherapy was better but with variable efficacy (20-100%). The most effective result (70-100% virus eradication) was obtained by combining chemotherapy with cryotherapy, or by consecutive chemotherapy, combined chemotherapy and thermotherapy, then cryotherapy treatments irrespective of cultivar. Regrowth following the two best virus eradication treatments was similar ranging from 8.6 to 29% across the three cultivars. The importance of virus removal on yield was reflected in "Dunluce" free of PVS having higher numbers of microtubers and in "V500' free of PVS and PVA having a greater proportion of microtubers > 5 mm. Our improved procedure has potential for producing virus-free planting material for the potato industry. It could also underpin the global exchange of virus-free germplasm for conservation and breeding programs.

5.
Arch Virol ; 166(5): 1395-1399, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33619582

RESUMO

We report the complete genome sequence of a novel virus isolated from Nandina domestica 'Firepower' in Auckland, New Zealand. It was mechanically transmitted to Nicotiana species, although all of these infections were symptomless. The complete genome of the new virus is 8892 nucleotides (nt) long, excluding the 3' poly(A) tail, contains three open reading frames (ORF), and is most closely related to citrus leaf blotch virus (CLBV) Actinidia isolate (CLBV-Act; 72% nt sequence identity), a member of the genus Citrivirus. Replicase and coat proteins, encoded by genome ORFs 1 and 3 respectively, shared 81-83% and 76-79% amino acid (aa) sequence identity, respectively, with CLBV-Act. Computer-based analysis suggests that this novel virus is the result of recombination between CLBV-Act and an unknown virus, highlighting the importance of this phenomenon for betaflexivirus evolution.


Assuntos
Berberidaceae/virologia , Flexiviridae/genética , Sequência de Aminoácidos , Sequência de Bases , Flexiviridae/classificação , Flexiviridae/fisiologia , Genoma Viral/genética , Especificidade de Hospedeiro , Nova Zelândia , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/virologia , RNA Viral/genética , Recombinação Genética , Proteínas Virais/genética
6.
Cyberpsychol Behav Soc Netw ; 21(11): 687-693, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30421996

RESUMO

This study expands on game character perspective-taking effects on political opinions while controlling for players' social dominance orientation or inclination for inequality among social groups. Random assignment to play a game as an immigration inspector decreased intention, subjective norms, and self-efficacy to help immigrants relative to baseline scores. The scores of participants randomly assigned to play a game similar in style but instead featuring the role of a newspaper editor remained unchanged. Within-subjects effects implied that baseline reductions in intention, subjective norms, and self-efficacy to help immigrants were solely attributed to playing games as game immigration inspectors. The study provides initial evidence that taking on the perspective of game characters can influence players' opinions about political issues, such as immigration.


Assuntos
Atitude , Intenção , Desempenho de Papéis , Autoeficácia , Jogos de Vídeo/psicologia , Emigrantes e Imigrantes , Feminino , Comportamento de Ajuda , Humanos , Masculino , Política , Distribuição Aleatória
7.
Anim Biotechnol ; 29(1): 34-40, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-28358238

RESUMO

122 randomly selected Vrindavani cattle were studied to detect polymorphism in four fragments of the CatSper2 gene that were comprised of exon 2, 4, 5, and 6 with flanking regions. Using PCR-SSCP and sequencing analysis, three SNPs (T157C, C273A, and A274C) in the first fragment, one SNP (C30G) in the second fragment, and two SNPs (T86G and T292C) in the fourth fragment were identified. The third fragment did not reveal any polymorphism. The SNPs were used for construction of haplotypes and three haplotypes were found. The least square analysis of variance revealed a significant (P < 0.01) effect of haplotype on all three motility parameters. The haplotype II and III were nonsignificantly different from each other while being significantly (P < 0.01) different from haplotype I. The nonsignificant difference of haplotype II with III can lead to a hypothesis that T>G or C>T SNPs may not play a role in sperm motility. However, when the comparison was made between haplotype I and II, it can be inferred that C>T SNP may have a role in sperm motility, as haplotype II has better motility parameters. Expression profiling of Catper2 gene revealed nonsignificant down regulation of CatSper2 gene in poor motility sperm compared to good motility sperm.


Assuntos
Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Bovinos/fisiologia , Haplótipos/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo , Motilidade dos Espermatozoides/genética , Espermatozoides/fisiologia , Animais , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Masculino
8.
Arch Virol ; 162(2): 591-595, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27812834

RESUMO

We present the first complete genome of vanilla mosaic virus (VanMV). The VanMV genomic structure is consistent with that of a potyvirus, containing a single open reading frame (ORF) encoding a polyprotein of 3139 amino acids. Motif analyses indicate the polyprotein can be cleaved into the expected ten individual proteins; other recognised potyvirus motifs are also present. As expected, the VanMV genome shows high sequence similarity to the published Dasheen mosaic virus (DsMV) genome sequences; comparisons with DsMV continue to support VanMV as a vanilla infecting strain of DsMV. Phylogenetic analyses indicate that VanMV and DsMV share a common ancestor, with VanMV having the closest relationship with DsMV strains from the South Pacific.


Assuntos
Genoma Viral , Filogenia , Potyvirus/genética , RNA Viral/genética , Vanilla/virologia , Sequência de Aminoácidos , Mapeamento Cromossômico , Fases de Leitura Aberta , Doenças das Plantas/virologia , Polinésia , Potyvirus/classificação , Potyvirus/isolamento & purificação , Análise de Sequência de DNA
10.
Arch Virol ; 161(2): 269-77, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26526146

RESUMO

Lettuce necrotic yellows virus (LNYV) is the type member of the genus Cytorhabdovirus, family Rhabdoviridae, and causes a severe disease of lettuce (Lactuca sativa L.). This virus has been described as endemic to Australia and New Zealand, with sporadic reports of a similar virus in Europe. Genetic variability studies of plant-infecting rhabdoviruses are scarce. We have extended a previous study on the variability of the LNYV nucleocapsid gene, comparing sequences from isolates sampled from both Australia and New Zealand, as well as analysing symptom expression on Nicotiana glutinosa. Phylogenetic and BEAST analyses confirm separation of LNYV isolates into two subgroups (I and II) and suggest that subgroup I is slightly older than subgroup II. No correlation was observed between isolate subgroup and disease symptoms on N. glutinosa. The origin of LNYV remains unclear; LNYV may have moved between native and weed hosts within Australia or New Zealand before infecting lettuce or may have appeared as a result of at least two incursions, with the first coinciding with the beginning of European agriculture in the region. The apparent extinction of subgroup I in Australia may have been due to less-efficient dispersal than that which has occurred for subgroup II - possibly a consequence of suboptimal interactions with plant and/or insect hosts. Introduction of subgroup II to New Zealand appears to be more recent. More-detailed epidemiological studies using molecular tools are needed to fully understand how LNYV interacts with its hosts and to determine where the virus originated.


Assuntos
Evolução Molecular , Variação Genética , Lactuca/virologia , Doenças das Plantas/virologia , Rhabdoviridae/classificação , Rhabdoviridae/genética , Austrália/epidemiologia , Análise por Conglomerados , Epidemiologia Molecular , Dados de Sequência Molecular , Nova Zelândia/epidemiologia , Nucleocapsídeo/genética , Filogenia , RNA Viral/genética , Rhabdoviridae/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência
11.
J Virol Methods ; 221: 100-5, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25962536

RESUMO

Apple scar skin viroid (ASSVd) is an important quarantine pathogen for international movement of pome germplasm as it can cause significant damage to pip fruit. A one-step real-time RT-PCR assay was developed for the rapid and sensitive detection of ASSVd. The assay was able to detect a wide range of ASSVd isolates and was highly specific compared to a published conventional RT-PCR. The detection limit of the new assay was estimated to be about 100 copies of the ASSVd target. The assay can be run as a duplex with the nad5 internal control primers and probe to simultaneously check the PCR competency of the samples therefore reducing the risk of false negatives. It is expected that this real-time RT-PCR assay will facilitate efficient testing for ASSVd by regulatory services, and will also have a wider use for the general detection of ASSVd in a range of pip fruit.


Assuntos
Malus/virologia , Reação em Cadeia da Polimerase Multiplex/métodos , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Viroides/isolamento & purificação , Virologia/métodos , RNA Viral/genética , Fatores de Tempo , Viroides/genética
12.
J Virol Methods ; 201: 38-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24566000

RESUMO

A real-time TaqMan RT-PCR assay was developed for the rapid and sensitive detection of Tomato ringspot virus (ToRSV), an important plant virus which infects a wide range of fruit and ornamental crops. Primers and a probe were designed based on the highly conserved 3'-untranslated region (UTR) sequences of ToRSV, to amplify a 182bp fragment of this region of RNA-1 and RNA-2. The assay was demonstrated to reliably amplify all ToRSV isolates tested. The detection limit was estimated to be about 12 copies of the ToRSV target region. No amplification was observed from the RNA of other nepoviruses or healthy host species. A comparison with a published conventional RT-PCR and a SYBR-based qRT-PCR indicated that both of the published assays lacked reliability and sensitivity, as neither were able to amplify all ToRSV isolates tested, and both were approximately 1000 times less sensitive than the novel TaqMan real-time assay. This TaqMan real-time assay was tested using four different reagent kits and was shown to be robust and stable, with no significant differences in sensitivity between kits. It is expected that the implementation of this TaqMan real-time RT-PCR assay will facilitate efficient phytosanitary certification of nursery stock requiring testing for ToRSV by regulatory agencies, and will also have wider uses for the general detection of ToRSV in a range of hosts.


Assuntos
Regiões 3' não Traduzidas , Nepovirus/isolamento & purificação , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Primers do DNA/genética , Nepovirus/genética , Sondas de Oligonucleotídeos/genética , Doenças das Plantas/virologia , Sensibilidade e Especificidade
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