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1.
Neotrop Entomol ; 53(2): 455-459, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38194154

RESUMO

Bermudagrass (Cynodon dactylon (L.) Pers., Poaceae) is one of the most important pasture grasses used in milk production systems in southern Brazil, with an increasing expansion of cultivated areas in recent years. Here, we report the first occurrence of the planthopper Metadelphax propinqua (Fieber) (Hemiptera: Delphacidae) feeding on bermudagrass in Brazil. Population outbreaks of this species were observed in January/February 2023 in a commercial hay production farm in the municipality of Chapecó, Santa Catarina State, southern Brazil. Metadelphax propinqua was found in association with three cultivars of C. dactylon (Tifton 85, Jiggs, and Vaquero). The infested plants showed leaf chlorosis and a reduced plant growth rate due to sap sucking and toxin injection as well as honeydew deposition on the leaves, which led to the development of sooty mold. In addition, this delphacid species has been reported as a vector of important pathogens to bermudagrass species and other row crops. Thus, M. propinqua is a potential pest of bermudagrass in Brazil and should be monitored to assess its establishment and behavior in Brazilian pasturelands.


Assuntos
Cynodon , Hemípteros , Animais , Brasil , Poaceae , Produtos Agrícolas
2.
Eval Health Prof ; 47(1): 133-138, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38065535

RESUMO

The posture undergoes changes during aging and may serve as a marker for the evaluation of the thoracic spine. This study aimed to correlate the variables for the evaluation of thoracic spine mobility and propose predictive equation models from the measurements of the thoracic Schober test and the digital inclinometer in older adults. The mobility of thoracic flexion and extension by levels (T1, T8 and T12) of 41 older adult subjects (66 ± 7 years) was quantified with a digital inclinometer (degrees) and Schober's test (cm). There was a moderate positive correlation between the digital inclinometer and the Schober test at T1 (r = .69), T12 (r = .60), and total flexion levels T1 to T12 (r = .74). Simple linear regression equations showed that thoracic Schober predicts thoracic mobility measures for these same levels. Moderate to strong correlations were observed between the inclinometer and the Schober Test measurements. The development of predictive equation models based on the thoracic Schober test could potentially enhance the ability to predict spinal mobility in physically independent older adults.


Assuntos
Postura , Humanos , Idoso , Amplitude de Movimento Articular
3.
Arch Virol ; 167(3): 989-993, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35112198

RESUMO

Since 1948, pale yellow wheat spike have been reported in southern Brazil. This symptom was associated with tenuiviruses due to the observation of cytoplasmic inclusions constituted by a mass of filamentous particles (7-10 nm in diameter) with indeterminate length, identical to those found in "leaf dip" preparations. Such symptoms are still seen in wheat crops; however, there is a lack of information regarding this pathosystem. Decades after the first report, the first sequences of wheat white spike virus were characterized. Wheat plants with symptoms such as pale yellowing, chlorotic streaks, and leaf mosaic were collected in Paraná State, Southern Brazil. High-throughput sequencing was used to determine the nearly complete nucleotide sequence of the viral genome. The genome is composed of five RNAs with a total size of 18,129 nucleotides, with eight open reading frames (ORFs). The virus identified in this study can be included in a new species in the family Phenuiviridae, genus Tenuivirus, and we have tentatively named this virus "wheat white spike virus".


Assuntos
Doenças das Plantas/virologia , Tenuivirus , Triticum/virologia , Brasil , Filogenia , Tenuivirus/classificação
4.
Arch Virol ; 166(6): 1763-1767, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33755801

RESUMO

Rice (Oryza sativa L.) is an important food crop for humanity, being cultivated in tropical and temperate regions of the world. This study reports the nearly complete genome sequences of four Brazilian rice stripe necrosis virus (RSNV) isolates. The nucleotide sequences of the RNA1 and RNA2 genome segments of these Brazilian isolates were 96.5 to 99.9% identical, indicating their close phylogenetic relationship to each other. Phylogeny and recombination analysis indicated that the genome of one of the isolates consisted of RNA segments of different origins, suggesting that a reassortment event had occurred.


Assuntos
Oryza/virologia , Vírus de Plantas/genética , Brasil , Filogenia
5.
Arch Virol ; 164(11): 2805-2810, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31451963

RESUMO

Physalis peruviana is a perennial solanaceous plant that has recently been established as a commercial crop in Brazil. This work reports the near-complete genome sequence, particle morphology, and plant host responses to a putative new sobemovirus, named "physalis rugose mosaic virus". The virus, characterized by isometric particles of ca. 30 nm in diameter, causes foliar symptoms of mosaic, malformation and blistering, accompanied by stunting. The near-complete genome sequence comprises 4175 nucleotides and contains five open reading frames that are similar to those of other sobemoviruses. In addition to P. peruviana, the new virus systemically infected Capsicum annuum, Nicotiana tabacum and Solanum lycopersicum by mechanical inoculation. Thus, this virus may cause disease in these crops in the field.


Assuntos
Genoma Viral/genética , Vírus do Mosaico/classificação , Vírus do Mosaico/crescimento & desenvolvimento , Physalis/virologia , Doenças das Plantas/virologia , Vírus de Plantas/classificação , Vírus de Plantas/genética , Brasil , Capsicum/virologia , Solanum lycopersicum/virologia , Vírus do Mosaico/genética , Vírus de Plantas/crescimento & desenvolvimento , RNA Viral/genética , Nicotiana/virologia
6.
Sci Rep ; 8(1): 14589, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30275487

RESUMO

The Bemisia tabaci is a polyphagous insect and a successful vector of plant viruses. B. tabaci is a species complex and in Brazil native species from the New World (NW) group, as well as the invasive species, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) were reported. For better understanding the distribution of the different species four years after the Mediterranean species invasion in Brazil, whiteflies were collected from 237 locations throughout the country between the years of 2013 and 2017, species were identified and the facultative endosymbionts detected. The survey revealed that MEAM1 was the prevalent species found on major crops across Brazil. It is the only species present in North, Northwestern and Central Brazil and was associated with virus-infected plants. MED was found in five States from Southeast to South regions, infesting mainly ornamental plants and was not associated with virus-infected plants. The prevalent endosymbionts identified in MEAM1 were Hamiltonella and Rickettsia; and the mtCOI analysis revealed low genetic diversity for MEAM1. In contrast, several different endosymbionts were identified in MED including Hamiltonella, Rickettsia, Wolbachia and Arsenophonus; and two distinct genetic groups were found based on the mtCOI analysis. Monitoring the distribution of the whiteflies species in Brazil is essential for proper management of this pest.


Assuntos
Alphaproteobacteria/isolamento & purificação , Gammaproteobacteria/isolamento & purificação , Hemípteros/classificação , Hemípteros/crescimento & desenvolvimento , Espécies Introduzidas , Filogeografia , Simbiose , Alphaproteobacteria/classificação , Alphaproteobacteria/genética , Animais , Brasil , Complexo IV da Cadeia de Transporte de Elétrons/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Variação Genética , Hemípteros/genética , Hemípteros/microbiologia
7.
J Biotechnol ; 269: 1-7, 2018 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-29408198

RESUMO

Apple stem pitting virus (ASPV), Apple chlorotic leaf spot virus (ACLSV) and Apple stem grooving virus (ASGV) are several major viral pathogens of apple trees, responsible for substantial damage to the world's apple industry. This study aimed to evaluate the effectiveness of the encapsulation-dehydration cryopreservation technique to eradicate these viral pathogens from in vitro shoot tips excised from 'Marubakaido' apple rootstock cultures. Axillary shoot tips were excised from in vitro cultures, encapsulated in alginate beads, precultured in MS salts, dehydrated in a laminar flow hood, immersed in liquid nitrogen, then warmed and recovered on medium. After LN exposure, in vitro rooting and acclimatization, recovered 'Marubakaido' plants exhibited 52% survival and 35% regrowth without callus formation. After 8 months of regrowth, PCR analyses revealed that all the plants were free of ACLSV and ASPV, but 2 out of 20 recovered plants were still infected with ASGV. This is the first report in Brazil of the application of cryotherapy to eradicate viral complexes in Malus. Cryotherapy can facilitate the production of virus-free plants by producing high quality plant material.


Assuntos
Criopreservação , Desidratação , Malus , Doenças das Plantas , Vírus de Plantas , Flexiviridae/isolamento & purificação , Flexiviridae/patogenicidade , Malus/fisiologia , Malus/virologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Raízes de Plantas/fisiologia , Raízes de Plantas/virologia , Brotos de Planta/fisiologia , Brotos de Planta/virologia , Vírus de Plantas/isolamento & purificação , Vírus de Plantas/patogenicidade , RNA Viral/análise
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