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Single crystals of DL-valine and DL-lysine hydrochloride were grown by slow evaporation method and the crystallographic structure were confirmed by X-ray diffraction experiment and Rietveld method. These two crystals have been studied by Raman spectroscopy in the 25–3600 cm −1 spectral range and by infrared spectroscopy through the interval 375–4000 cm −1 at room temperature. Experimental and theoretical vibrational spectra were compared and a complete analysis of the modes was done in terms of the Potential Energy Distribution (PED).

Many methods can be used for arriving in a correct virus disease diagnose, and the serological techniques are the most used methods for plant virus identification. The indirect enzyme-linked immunosorbent assay (Indirect-ELISA) or plate-trapped antigen ELISA (PTA-ELISA) has been useful for detection of viruses in a wide range of situations, especially to test a large number of samples in a relatively short period of time. Immune-biological Companies have developed practical kits for direct ELISA or double antibody sandwich (DAS-ELISA), but neither Company has developed kits for PTA-ELISA. As a single universal antibody-conjugate is used for detection of a wide range of plant viruses, the PTA-ELISA technique is more economical, practical and suitable for virus detection. Considering also the great problem of including infectious plant viruses in DAS-ELISA kits, a simple kit for PTA-ELISA was developed for plant virus identification. Extracts from infected plant tissues were added into the ELISA plate wells, which were sealed with plastics and maintained in the refrigerator and Laboratory conditions for different periods of time. The plates were tested by the regular PTA-ELISA and after 20 months of incubation, the plate showed excellent results when used for detection of six virus species from the genera Comovirus, Cucumovirus, Potyvirus and Sobemovirus in infected plant tissues. The ELISA plate trapped virus together with its specific antiserum could constitute a simple kit, which will permit the exchange of antisera among virologists without transferring infectious viruses from one laboratory to another to be used as control. RESUMO Muitos métodos podem ser utilizados para uma correta diagnose de doenças ocasionadas por vírus, e os métodos sorológicos são os mais utilizados. O teste de ELISA "enzyme-linked immunosorbent assay" indireto ou placa tratada com antígeno (PTA-ELISA) é realizado para detecção de vírus em várias situações, especialmente para testes de elevado número de amostras em curto período de tempo. Empresas que comercializam imunobiológicos têm desenvolvido kits práticos de ELISA direto ou ELISA sanduíche duplo (DAS-ELISA), mas nenhuma delas desenvolveu kits de ELISA indireto ou PTA-ELISA. Como um anticorpo universal conjugado a uma enzima é usado na técnica de PTA-ELISA para detecção de vasta gama de vírus, PTA-ELISA é a técnica mais econômica, prática e adequada. Considerando também o problema da inclusão de vírus como controle positivo em kits comerciais de DAS-ELISA, um kit sorológico de PTA ELISA foi desenvolvido para identificação de vírus de planta. Extratos de tecidos infetados foram adicionados a poços de placas de ELISA, que após lavagem e secagem foram seladas com adesivo plástico e mantidas em refrigerador e em condições de laboratório por diferentes períodos. Após 20 meses de incubação, as placas do kit mostraram excelentes resultados na detecção de seis espécies de vírus dos gêneros Comovirus, Cucumovirus, Potyvirus e Sobemovirus. Placas de ELISA previamente tratadas com vírus, juntamente com antissoros específicos podem constituir um kit de PTA-ELISA, que proporcionará eficiente diagnose de viroses vegetais e permitirá permuta de antissoros entre grupos científicos sem a transferência de vírus infectivo de um laboratório para outro.

In this work the vibrational properties of d -methionine crystal submitted to high pressure were investigated through Raman spectroscopy. The measurements covered the pressure range from 0.0 to 7.0 GPa. From the analysis of the spectra we were able to identify two reversible pressure induced phase transitions: the first at 2.0 GPa and the second at 2.5 GPa. The three phases are characterized by different number of peaks associated with the rocking of ( C O 2 − ) and with the stretching of CSC, among others. A comparison between the behavior of d -methionine and l -methionine under high pressure is furnished as well as a discussion about the symmetries of the crystal in the two high pressure phases.

Plant virus identification and characterization can be accomplished by several methods involving their morphological, physical, biological, cytological, serological and molecular properties. The use of molecular techniques is increasing worldwide, and some have been developed for identification and characterization of plant viruses. Reverse transcription polymerase chain reaction (RT-PCR) has been shown to be a suitable method for research with RNA plant viruses. In this study, a new approach of RT-PCR involving previous virus immunoprecipitation (IP) was used for RNA amplification of five virus species of the genera Comovirus, Cucumovirus, Potyvirus and Sobemovirus from infected plant tissues. IP-RT-PCR was practical, sensitive and minimized problems with total RNA extractions from infected tissues. The technique provides partial virus particle purification by its specific immunoprecipitation, and it should be especially useful for RNA amplification of viruses that occur in low or variable concentrations in plant tissues or when the tissues contain various forms of RT-PCR amplification inhibitors.

We have obtained the Raman spectra of dl -leucine crystal through a diamond anvil cell for pressures between 0 and 5 GPa. The observation of several anomalies in the regions of both the lattice mode and the internal mode suggests that the crystal undergoes a phase transition between 2.4 and 3.2 GPa. This phase transition is preceded by a gradual change of the molecular conformation of leucine molecules in the unit cell. We show that, up to 5 GPa, the dl -leucine crystal is more stable than the chiral l -leucine crystal because while the former presents only one phase transition in the 2.4–3.2 GPa interval, the latter presents three different transitions, the first of which is observed at 0.46 GPa. Additionally, when pressure is released to 0.0 GPa, the original Raman spectrum is recovered, indicating that the modification at high pressure on dl -leucine crystal is reversible.

The identification of source of resistance in cultivated cucurbits species is very important for the development of resistant cultivars to control diseases caused by virus from the genus Potyvirus. The present research had the objective to evaluate the phenotypic reactions and the behavior of pumpkin (Cucurbita spp.) accessions to the virus species from the genus Potyvirus: Papaya ringspot virus type Watermelon (PRSV-W), Zucchini yellow mosaic virus (ZYMV) and Watermelon mosaic virus (WMV). Twenty-eight accessions of pumpkin from the Cucurbit Germplasm Bank from Embrapa Semiárido, Petrolina, PE, Brazil were evaluated. Twelve young plants from each pumpkin accession were inoculated with each one of the virus species and were maintained at greenhouse for their symptom reaction evaluations. All possible virus infections or absence of infection were confirmed by plate-trapped antigen enzyme linked immunosorbent assay (PTA-ELISA) against antisera specific to PRSV-W, ZYMV and WMV at the Plant Virus Laboratory, Universidade Federal do Ceará. Three pumpkin accessions showed extreme resistant to WMV and eight accessions presented mild mosaic when inoculated with PRSV-W. The most severe symptoms were observed on those accessions inoculated with ZYMV and 50% of the accessions showed to be highly susceptible. On the other hand, the pumpkin accessions inoculated with WMV presented the mildest symptoms, indicating that 39% of them were resistant, and 39% were tolerant. The Cucurbita spp. accessions BGC 518, BGC 530, BGC 567, and BGC 683 that showed resistance to one or more than one virus species constitute promising sources of resistance for developing virus resistant pumpkin cultivars or hybrids.

Passion fruit (Passiflora edulis) and cowpea (Vigna unguiculata) are two agricultural crops of considerable economic importance in Northeastern Brazil. Fruit woodiness caused by isolates of Cowpea aphid-borne mosaic virus biotype P (CABMV-P) is the most important virus disease that occurs on passion fruit in Brazil and the biotype cowpea (CABMV-C) is responsible for the most common and important virus disease of cowpea in Northeastern Brazil. The objective of the present research was to determine the biological relationships between isolates of biotype CABMV-C obtained from cowpea (CABMV-CFor and CABMV-CBv) and isolates of biotype CABMV-P obtained from passion fruit (CABMV-PMild and CABMV-PSevere) in common hosts. In host range studies involving 25 plant species only Canavalia ensiformis and Macroptilium lathyroides were shown to be common systemic hosts for all virus isolates. Cross protection studies were developed between CABMV-PMild and CABMV-PSevere in passion fruit and between CABMV-PSevere and CABMV-CFor in C. ensiformis. Unilateral cross protection was detected between CABMV-PSevere and CABMV-CFor in C. ensiformis, but CABMV-PMild did not cross protect passion fruit against CABMV-PSevere. RESUMO Maracujazeiro (Passiflora edulis) e feijoeiro caupi (Vigna unguiculata) são duas culturas economicamente importante para o Nordeste do Brasil. O endurecimento dos frutos causado por isolados de Cowpea aphid-borne mosaic virus biótipo P (CABMV-P) é a virose mais importante que ocorre no maracujazeiro no Brasil e o biótipo caupi (CABMV-C) é responsável pela virose mais comum e importante que afeta o feijoeiro caupi. O objetivo desta pesquisa foi determinar as relações biológicas entre isolados do biótipo CABMV-C obtido de feijoeiro caupi (CABMV-CFor e CABMV-CBv) e isolados do biótipo CABMV-P obtidos de maracujazeiro (CABMV-PFraco e CABMV-PSevera) em hospedeiros comuns. Em estudos de gama de plantas hospedeiros, envolvendo 25 espécies de plantas, somente Canavalia ensiformis e Macroptilium lathyroides mostraram ser hospedeiros sistêmicos comuns a todos os isolados virais. Estudos de proteção cruzada foram desenvolvidos entre CABMV-PFraco e CABMV-PSevero em maracujazeiro e CABMV-PSevero e CABMV-CFor em C. ensiformis. Proteção cruzada unilateral foi detectada entre CABMV-PSevero e CABMV-CFor em C. ensiformes, mas CABMV-PFraco não protegeu maracujazeiro contra o CABMV-PSevero.

Mixed infections in cucurbits are frequently observed in natural conditions between viruses from the Potyvirus genus and Cucumber mosaic virus (CMV), which significantly decreases productivity. The objectives of the present study was to compare the host range of PRSV-W, WMV, and ZYMV isolates and evaluate the effects of mixed infections with CMV in zucchini plants (Cucurbita pepo L.). Host range studies comprising 23 plant species confirmed some similarities and biological differences among the isolates of PRSV-W, ZYMV, and WMV. RT-PCR confirmed the amplification of DNA fragments of the PRSV-W, WMV, and ZYMV coat protein gene (cp) and cytoplasm inclusion gene (ci). The virus interaction studies in zucchini Caserta plants indicated synergistic interactions, particularly among species from the Potyvirus genus, and some CMV interference with some virus combinations. Infecções mistas em cucurbitáceas são observadas com grande frequência em condições naturais entre os vírus do gênero Potyvirus e o Cucumber mosaic virus (CMV), reduzindo significativamente a produtividade das culturas. Os objetivos deste trabalho foram comparar a gama de hospedeiras de isolados de PRSV-W, WMV e ZYMV e avaliar os efeitos de infecções mistas entre esses isolados e um isolado de CMV em abobrinha (Cucurbita pepo) cv. Caserta. Estudos de gama de plantas hospedeiras, envolvendo 23 espécies vegetais confirmaram similaridades e diferenças biológicas entre PRSV-W, ZYMV e WMV. Estudos moleculares com RT-PCR possibilitaram a amplificação de fragmentos de DNA para as regiões do gene da CP (cp) e do gene da CI (ci) de PRSV-W, WMV e ZYMV. Estudos sobre interação sinérgica entre os vírus do gênero Potyvirus e CMV em abobrinha cv. Caserta evidenciaram efeitos sinérgicos, sobretudo entre as espécies do gênero Potyvirus e interferência do CMV em algumas combinações.

Visando verificar a ocorrência de vírus em cultivos de feijoeiro-caupi (Vigna unguiculata), foram realizadas visitas de inspeção a campos de produção dos municípios de Bom Sucesso, Paulista e Pombal, no estado da Paraíba, durante os meses de agosto a dezembro de 2009 e de fevereiro a maio de 2010. Amostras foliares com sintomas típicos de mosaico e deformação foliar foram coletadas e analisadas por "enzyme linked immunosorbent assay" (ELISA) indireto contra anti-soros específicos para Cowpea aphid-borne mosaic virus (CABMV) e Cucumber mosaic virus (CMV) e por dupla difusão em ágar contra anti-soro para Cowpea severe mosaic virus (CPSMV). Cinco amostras coletadas com sintomas de mosaico dourado no município de Pombal na época chuvosa foram submetidas à detecção molecular por meio de "Polymerase Chain Reaction" (PCR) para Begomovirus. A ocorrência de CPSMV e CABMV foi observada nos campos de produção dos três municípios visitados nas duas épocas de cultivo analisadas, em infecções simples e mistas. A presença de vírus do gênero Begomovirus foi confirmada em amostras foliares com sintomas de mosaico dourado. Entretanto, estudos adicionais serão necessários para a identificação da espécie. CMV não foi detectado em nenhum dos municípios analisados.

Cowpea (Vigna unguiculata) is an important crop of the traditional agriculture system in the Northeast of Brazil. It can be infected by more than 20 virus species and Cowpea severe mosaic virus (CPSMV) is one of the most important pathogens that naturally infect cowpea in Brazil. Several CPSMV isolates were obtained and characterized in the Plant Virus Laboratory at the Federal University of Ceará: CPSMV-CE - the first characterized isolate of the virus obtained from cowpea in the State of Ceará; CPSMV-AL - isolated from cowpea in Alagoas; CPSMV-PE - isolated from cowpea in Pernambuco; CPSMV-PR - obtained from soybean (Glycine max) in Paraná and CPSMV-CROT - isolated from Crotalaria paulinea, in Maranhão. An isolate of CPSMV with the property to infect the cv. Macaibo, a cowpea cultivar immune to most of CPSMV isolates was also biologically and serologically characterized as a new strain of the virus (CPSMV-MC). The CPSMV-MC was isolated in January 1990 and has been evaluated over 20 years by host range studies and maintenance in vivo by periodical mechanical inoculations in cowpea. The results of this periodical evaluation revealed that the biological integrity and the serological properties of CPSMV-MC were preserved over 20 years, indicating that the genetic preservation of a virus strain could occur over the years. Molecular studies involving part of the coat protein (CP) gene of CPSMV-MC and five other Brazilian CPSMV isolates indicated a high degree of conservation, with 92-100% nucleotide sequence identity among the isolates. O feijão-caupi (Vigna unguiculata) é uma cultura do sistema tradicional do Nordeste do Brasil, que pode ser infetada por mais de 20 espécies de vírus, sendo o vírus do mosaico severo do caupi (Cowpea severe mosaic virus, CPSMV) um dos mais importantes patógenos que infeta naturalmente essa leguminosa no Brasil. Vários isolados do CPSMV foram obtidos e caracterizados no Laboratório de Virologia Vegetal da UFC: CPSMV-CE - o primeiro isolado do vírus obtido no Ceará; isolados obtidos de feijão-caupi: CPSMV-AL (Alagoas) and CPSMV-PE (Pernambuco); CPSMV-PR - isolado de soja (Glycine max) no Paraná e CPSMV-CROT - isolado de Crotalaria paulinea no Maranhão. Um isolado de CPSMV capaz de infetar o cv. Macaibo, cultivar de ffeijão-caupi imune a todos os demais isolados de CPSMV foi biológica e sorologicamente caracterizado e designado de CPSMV-MC. O CPSMV-MC obtido em janeiro de 1990 vem sendo avaliado através de estudos de gama de hospedeiro e mantido in vivo através de inoculações periódicas em feijão-caupi. Os resultados dessas avaliações revelaram que a integridade biológica e as propriedades sorológicas do CPSMV-MC foram preservadas ao longo dos anos, indicando que a preservação das propriedades genéticas de uma estirpe viral pode acontecer através dos anos. Estudos moleculares adicionais revelaram que a seqüência de nucleotídeos correspondente a parte do gene da capa protéica de cinco isolados de CPSMV, incluindo o CPSMV-MC, possui elevado grau de conservação, com 92-100% da seqüência de nucleotídeos idêntica entre os isolados.

Raman spectroscopy was used to investigate the vibrational properties of l -glutamic acid in the β-form in a diamond-anvil cell up to pressures of 21.5 GPa in the spectral region between 20 and 3270 cm −1 . From the analysis of the results it was observed that the crystal undergoes an impressive series of phase transitions in this pressure range. The phase transitions are accompanied by modifications in a number of modes and discontinuities in the wavenumber versus pressure plots, as well as by modifications in the bands associated to both rocking and stretching modes of NH 3 + . Upon decompression to ambient pressure the original spectra were recovered indicating that the phase transitions are reversible.

In this article, we report a high-pressure Raman spectroscopy study of palmitic acid (PA, C form) from ambient pressure up to 21 GPa. The effects of hydrostatic pressure on the vibrational spectrum of PA are reported, and the data show that PA experiences a rich sequence of phase transformations. These changes in the crystal structure occur gradually as the pressure increases and they are related to the highly flexible crystalline structure. Copyright c � 2011 John Wiley & Sons, Ltd.

Temperature dependent Raman study of l -ascorbic acid has been performed from 15 to 418 K. Changes in the wavenumber vs. temperature plots for some internal modes were interpreted as conformational molecular change and the discontinuity in the wavenumber vs. temperature plots along with the appearance of a new vibrational mode in the temperature range 200–270 K suggests that l -ascorbic acid undergoes a structural phase transition. For temperatures higher than 300 K, no relevant modification was observed on the Raman spectra thus indicating a stable structure at high temperatures. Additionally, a correlation between OH stretching wavenumber and the behavior of hydrogen bond is also made.

Raman spectroscopy investigations of dl-alanine crystal under high pressures have been carried out up to 18.0 GPa. For instance, around 1.0 GPa and between 1.7 and 2.3 GPa changes in the Raman profile were observed and associated to conformational changes of the molecules in the unit cell or to a phase transition accompanied to slight conformational change of the molecule through CH and CH3 groups. Moreover, between 6.0 and 7.3 GPa, the appearance of a new low energy lattice modes and to the splitting of a band assigned to the stretching vibration of the CCH3 moiety were related to a second phase transition. Finally, changes in lattice modes, red shift of the band associated to CCH3 stretching and increasing of line-width of the band associated to the wagging of CO2, between 11.6 and 13.2 GPa, are ascribed to a third phase transition. On release of pressure the original phase was obtained again.

Pressure-dependent Raman scattering studies have been performed on stearic acid single crystal, C form. The vibrational spectra have been recorded in the 20–1200 cm−1 and in the 2800–3100 cm−1 spectral regions. The behavior of the Raman modes indicates that the crystal undergoes a series of structural modifications. The change observed between 0.8 and 1.27 GPa was associated with a conformational modification or tilting of the dimer. A second modification was observed at ∼2.5 GPa accompanied by jump of lattice mode frequencies, and the appearance and disappearance of bands. Finally, a third set of changes in the Raman band profile was observed between 3.3 and 3.8 GPa and was associated with another structural phase transition.

O vírus do amarelo letal do mamoeiro (Papaya lethal yellowing virus, PLYV) é responsável por uma das principais doenças do mamoeiro (Carica papaya) no Nordeste brasileiro. O PLYV pode ser transmitido através do solo, água, instrumento de corte e mãos contaminadas. A presente pesquisa teve como objetivo estudar as características biológicas, sorológicas e físicas de um isolado do vírus e avaliar sua sobrevivência em tecido seco infetado. O PLYV foi detectado por "Enzyme linked immunosorbent assay" (ELISA) indireto e isolado em mudas de mamoeiro, através da inoculação mecânica. A sobrevivência do PLYV em folhas e raízes secas de mamoeiro infetado foi avaliada por sorologia e inoculação em plantas sadias. A presença do vírus foi detectada em folhas e raízes de mamoeiro secas, indicando que o vírus pode permanecer ativo em restos de cultura por até 120 dias. A purificação do PLYV permitiu a obtenção de 309.5 mg de vírus/kg de folha e o anti-soro obtido mostrou-se altamente específico, com títulos de 1:128 em dupla difusão em Agar e 1:1.024.000 em Elisa indireto. Estudos das propriedades físicas do PLYV em mamoeiro revelaram um ponto de inativação térmica (PIT) em torno de 80 ºC, um ponto máximo de diluição (PMD) de ac. 10-6 e uma longevidade in vitro (LIV) acima de 50 dias. The Papaya lethal yellowing virus (PLYV) is responsible for one of the most important disease of papaya (Carica papaya) in the Northeast of Brazil. The PLYV can be transmitted through the soil, irrigation water, agriculture tools and contaminated hands. The present research had the objective to characterize biologically, serologically and physically a PLYV isolate and evaluates how long it survives in infected dried tissues. The PLYV was identified by indirect enzyme linked immunoabsorbent assay (ELISA), isolated in young papaya plants by mechanical inoculations and maintained at green house conditions for virus purification. Approximately 309.5 mg of virus was purified per kg of infected papaya leaves and a polyclonal antiserum was obtained from an immunized rabbit. The antiserum obtained was shown to be highly specific to PLYV with a titer of 1:128 in double immune-diffusion and a titer of 1:1.024.000 in indirect ELISA. The virus was detected in dried roots and leaves maintained at room temperature up to 120 days, confirming its high stability within nonliving plant tissues, which could explain its dissemination by contaminated hands, tools, water and soil. The physical properties determined for the virus revealed a thermal inactivation point of 80 ºC, longevity in vitro over 50 days and dilution end point ac. of 10-6.

Raman spectra of DL-Alanine crystals were investigated in the 50–3200 cm−1 spectral region for temperatures ranging from 15 to 295 K. The crystalline structure of DL-Alanine represents a rare example of an amino acid racemate crystallizing in a non-centrosymmetric space group. From this study, we have observed changes in the wavenumber of modes associated with both rocking of CO2− and skeletal vibrations. On the other hand, neither changes in the modes associated to CH or CH3 vibrations nor substantial modifications of the lattice modes of the crystal were observed. Such result indicates slight changes of the CO2 group orientation without observation of a solid–solid phase transition in the DL-Alanine crystal. Copyright © 2009 John Wiley & Sons, Ltd.

In this work we present a Raman scattering study of a specific region of the morphotropic phase boundary (MPB) of the [Pb(Mg1/3Nb2/3)O3]1−x (PbTiO3)x relaxor system. We performed low-temperature measurement for thex = 0.4 composition in the 20 – 300 K temperature range, and a detailed analysis of Raman spectra of x = 0. 4a ndx = 0.37 compositions at 180 K. The analysis of Raman spectra indicates a structural phase transition at around 170 K for x = 0.4. The comparison of Raman data from x = 0. 4a ndx = 0.37 compositions suggests different phases for these samples at 180 K. These results are in accordance with the tetragonal to monoclinic structural phase transition observed in the PMN – PT MPB and contribute to improve the knowledge of the MPB of this solid solution. Additionally, we have performed the lattice dynamics phonon calculation of the (1 − x )P MN –xPT relaxor in order to best understand its complex Raman spectral properties. The normal mode analyses (at q ∼ 0) were performed by considering tetragonal symmetry for the (1 − x )P MN –xPT system and using the rigid ion model and mean field approximation. Our calculated wavenumber values are in good agreement with experimental and calculated results reported for PbTiO3 thus providing a reliable assignment of the various Raman modes. The low wavenumber modes are interpreted as arising from a lifting of the degeneracy of the vibrational modes related to Mg, Nb and Ti sites. Copyright c � 2009 John Wiley & Sons, Ltd.

Raman spectra of deuterated L-alanine have been obtained at high-pressure conditions. A phase transition at ∼1.5 GPa associated with the splitting of some internal modes and increase of the wavenumber of the external modes was observed. Similarly to the hydrogenated L-alanine crystal, this first transition was related to a symmetry change. Moreover, further modifications of the Raman spectra were observed at 4.4 GPa, which may be associated to conformational changes of the molecule. To give further support to such a hypothesis, neutron powder diffraction measurements were performed. Information about the cell parameter at atmospheric pressure gave valuable information about the ND distances, shedding light on the behavior of the torsional vibration of ND3+. Copyright © 2009 John Wiley & Sons, Ltd.

Aiming to get information about the virus that most frequently infects cucurbit plants of the species Benincasa hispida,Citrullus spp., Cucurbita spp., Cucumis melo, Lagenaria sp., Momordica charantia and also some F1 hybrids of C. lanatus with C. lanatus var. citroides in irrigated areas of Petrolina-PE and Juazeiro-BA, experimental and farming areas were surveyed in the first and second half of each year (2005 to 2007). The samples were tested by indirect enzyme-linked immunosorbent assay (ELISA) against antisera specific for Papaya ringspot virus, type watermelon(PRSV), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV) and Cucumber mosaic virus (CMV), and by Agar Double Diffusion against antiserum specific for Squash mosaic virus (SqMV) at the Plant Virus Laboratory of the Federal University of Ceara. Leaf samples from 967 plants were analyzed and 608 of them were infected. Among 125 samples from symptomless plants, 42 allow replication. PRSV-W was predominant, followed by WMV and ZYMV, and mixed infections occurred in all infected species. CMV was detected only in one sample and SqMV was not found. This is an indication that a breeding program for virus resistance in cucurbit species in the region must consider the three potyviruses.

Raman scattering measurements were carried out on a single crystal of L-valine with the pressure increasing from the ambient value to 6.9 GPa. Sudden changes in intensity of the bands were observed in the higher energy spectral range at ∼3 GPa and ∼5.3 GPa. Discontinuities observed in the wave number vs. pressure plots occurred in the complete spectrum at those same pressures, suggesting changes in the crystal structure.

The mode assignment of the cubic phase of anhydrous Na2MoO4 was carried out on the basis of lattice dynamic calculation using the classical rigid-ion model. Temperature-dependent studies indicate that this crystal remains in the cubic structure in the 15–773 K range and undergoes a phase transition at around 783 K. The behavior of the Raman modes indicates that this transition is strongly first-order in nature and the phase above 773 K may have an orthorhombic symmetry. This transition is connected with tilting and/or rotations of the MoO4 tetrahedra, which lead to a disorder at the MoO4 sites. Our results give also evidence that the MoO bond lengths decrease in the high-temperature phase. Copyright © 2008 John Wiley & Sons, Ltd.

O Nordeste brasileiro possui condicoes edafoclimaticas favoraveis ao cultivo do meloeiro (Cucumis melo). No entanto, diferentes problemas fitossanitarios afetam sua produtividade, destacando-se as doencas ocasionadas por virus. A presente pesquisa objetivou efetuar a caracterizacao biologica e sorologica de um isolado de Squash mosaic virus (SqMV) obtido no Ceara. Em estudos de gama de hospedeiros o virus infetou sistemicamente somente cinco especies da familia Cucurbitaceae e ocasionou lesoes locais em Chenopodium amaranticolor e C. quinoa. Estudos da infeccao mista do SqMV com virus do genero Potyvirus demonstraram efeito sinergico entre os mesmos. A purificacao quimica do SqMV foi possivel a partir de plantas de meloeiro e a imunizacao em coelho com a preparacao purificada possibilitou a producao de antissoro policlonal especifico. O antissoro produzido apresentou titulos de 1:10.000 quando avaliado por plate trapped antigen enzyme linked immune absorbent assay (PTA-ELISA), de 1:160.000 em immune-precipitation ELISA (IP-PTA-ELISA) e de 1:1.024 em Dupla Difusao em Agar. Estudos do relacionamento sorologico entre SqMV e Cowpea severe mosaic virus (CPSMV) do genero Comovirus contra seus antissoros homologos e heterologos em Dupla Difusao em Agar demonstraram relacionamento unilateral entre os mesmos.

Por constituirem uma importante fonte de alimento, plantacoes de melancia e abobora sao comumente cultivadas no sertao paraibano, porem pouco se sabe sobre a ocorrencia de patogenos causadores de doencas, os quais limitam a sua produtividade e renda aos produtores. Visando obter informacoes sobre a ocorrencia dos patogenos virais e fungicos em cultivos de abobora e melancia situados em municipios produtores no sertao da Paraiba, amostras coletadas com sintomas de mosaico e deformacao foliar, tipicos de doencas virais foram analisadas pela tecnica sorologica “enzime linked immuno sorbentassay” (Elisa) indireto para Papaya ring spot virus, type watermelon (PRSV-W), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV) e Cucumber mosaic virus (CMV). O teste de dupla difusao em Agar foi utilizado para verificar a presenca de Squash mosaic virus (SqMV). Em contrapartida, amostras coletadas com sintomas de doencas fungicas foram analisadas pelo isolamento do patogeno e visualizacao de suas caracteristicas morfologicas em microscopio optico. Em abobora, houve prevalencia dos virus ZYMV e PRSV-W em infeccoes simples e mistas, e maior incidencia dos fungos Cladosporium spp., e Alternaria spp. Em melancia detectou-se infeccao simples e mistas das especies PRSV-W, WMV e ZYMV, e maior frequencia de Fusarium spp. e Alternaria spp.. Nao foram detectados os virus CMV e SqMV. Os resultados obtidos revelam a ocorrencia de varios patogenos fungicos e viroticos em cultivos de abobora e melancia situados no sertao da Paraiba e ressaltam a importância da utilizacao de estrategias de manejo que reduzem os danos ocasionados por esses patogenos. Occurrence of pathogens in watermelon and pumpkin crops in the State of Paraiba Abstract: By constitute an important food source, watermelon and pumpkin plantations are commonly grown on Paraiba backlands, but little is known about the occurrence of disease-causing pathogens, which limit their productivity and income to producers. With objective to get information about the viral and fungal pathogens occurrence in pumpkin and watermelon crops in producing counties located in the backlands of Paraiba, samples with symptoms of mosaic and leaf distortion, typical of viral etiology of disease were collected and analyzed by "Enzyme linked immune sorbentassay" (Elisa) Indirect for species Papaya ring spot virus , type watermelon (PRSV-W), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus ( ZYMV) and Cucumber mosaic virus (CMV). The double diffusion test in Agar was used to verify the presence of Squash mosaic virus (SqMV). In contrast, samples collected with fungal disease symptoms were analyzed based on the isolation of the pathogen and viewing their morphological characteristics under an optical microscope. In pumpkin, there was prevalence of ZYMV and PRSV-W in single and mixed infections, and higher incidence of Cladosporium spp. and Alternaria spp. On the other hand, in watermelon was detected single and mixed infections of PRSV-W, WMV and ZYMV species, and higher frequency of Fusarium spp. and Alternaria spp.. Were not detected the virus CMV and SqMV. The results show the occurrence of various fungal and viral pathogens in pumpkin and watermelon crops located in the backlands of Paraiba and emphasize the importance of using management strategies that reduce the damage caused by these pathogens.

O tomateiro, Lycopersicon esculentum Mill., hortaliça de grande importância econômica para o Brasil, apresenta muitos problemas fitossanitários, dentre os quais as viroses. Os vírus associados à cultura no país pertencem aos gêneros Begomovirus, mais frequentemente relatado, Potyvirus, Cucumovirus, Tospovirus e Tobamovirus. No Ceará, apesar de relatos da incidência de viroses em tomateiros na Chapada da Ibiapaba, maior região produtora do estado, há escassez de informações sobre a situação atual da ocorrência de begomovírus, nas diversas lavouras daquele agropólo. Assim, foram objetivos deste trabalho: realizar levantamento da presença de begomovírus nas cultivares e híbridos de tomateiro explorados comercialmente na Ibiapaba; verificar a ocorrência de plantas daninhas infectadas e investigar a transmissão artificial de begomovírus isolados de tomateiro e de plantas daninhas para tomateiro. Os testes sorológicos e a PCR realizados detectaram begomovírus em 'Alambra', 'Densus', 'Monalisa', 'Santa Clara', 'Sheila', 'Sofia', 'Raisa-N' e 'TY- Fanny', cultivares e híbridos mais cultivados nas lavouras. Além de begomovírus, Cucumber mosaic virus (CMV) e Potato virus Y (PVY) foram também detectados. As plantas daninhas Amaranthus spinosus, A. viridis, Ageratum conyzoides e Bidens pilosa foram identificadas como hospedeiras naturais de begomovírus. A transmissão de begomovírus de tomateiro para tomateiro ocorreu em inoculações por enxertia e via extrato foliar e de plantas daninhas infectadas para tomateiros sadios somente por enxertia. O levantamento revelou que, à semelhança do que ocorre no restante do país, begomovírus são predominantes nas lavouras de tomate da Ibiapaba e que as plantas invasoras ali encontradas podem ser fontes de infecção viral para a cultura.

Raman scattering investigations of surfactant solubilized SWCNTs under hydrostatic pressure were performed. The wave number dependence on pressure for the tangential bands was observed to be discontinuous at 2 GPa, with change of slope for higher pressures. This change coincides with the calculated critical pressure for collapse of the tubes. Therefore, it could be considered as indicative of deformation of the tube along the radial direction.

Single crystals of L-valine, C5H11O2N, have been studied by Raman spectroscopy at temperatures from 17 to 300 K over the spectral range 20–3300 cm−1. A tentative assignment of the bands is given. Careful analysis of the Raman spectra suggests that a series of changes in the low-wavenumber region may be associated with a phase transition undergone by the material, and this possibility is discussed. Copyright © 2005 John Wiley & Sons, Ltd.

Progênies de melão (Cucumis melo L.) cv. Tupã, um tipo que associa as características favoráveis do fruto do melão Amarelo e do melão Cantaloupe, foram submetidas à inoculação artificial com cinco vírus [Watermerlon mosaic virus (WMV-2), Papaya ringspot virus (PRSV-w), Zucchini yelow mosaic virus (ZYMV), Squash mosaic virus (SqMV) e Cucumber mosaic virus (CMV)], em casa de vegetação. A produção e a qualidade do fruto foram avaliadas em campo. Progênies de três famílias mostraram resistência ao PRSV-w e ao ZYMV, algumas manifestaram resistência também ao WMV-2. Cerca de 63,15% apresentaram resistência somente ao PRSV-w e 52,63% somente ao ZYMV. A resistência para a combinação do PRSV-w e ZYMV ocorreu em 42,10% das progênies e a resistência tripla a PRSV-w, ZYMV e WMV-2 em 36,84%. Uma progênie foi resistente aos quatro vírus (PRSV-w, ZYMV, WMV-2 e CMV). Para o caráter concentração de colheita o comportamento das progênies foi muito variável, observando-se progênies onde a metade dos frutos foram colhidos até os 80 dias, e outras onde até os 70 dias nenhum fruto havia sido colhido. Em relação ao tipo Amarelo, foram muito tardias para a maturação dos frutos, mas mostraram semelhanças com o fruto para peso médio, formato, diâmetro interno e espessura da polpa. A firmeza da polpa variou de 7,78 N a 35,6 N, sendo que em 20% das progênies a firmeza da polpa foi superior a 20 N, muito semelhante aos melões do tipo Cantaloupe.Progenies of melon (Cucumis melo L.) cv. Tupã, that associate the favorable fruit characteristics of yellow casaba cantaloupe types, were submitted to artificial inoculation with five virus: Watermerlon mosaic virus (WMV-2), Papaya ringspot virus (PRSV-W), Zucchini yellow mosaic virus (ZYMV), Squash mosaic virus (SqMV) and Cucumber mosaic virus (CMV), in greenhouse. Yield and the fruit quality were evaluated in the field. Progenies of three families showed marked resistance to PRSV-W and to ZYMV, also some manifested resistance to WMV-2. More than 50% showed isolated resistance to PRSV-W (63,15%) and to ZYMV (52,63%). The resistance to both PRSV-W and ZYMV occurred in 42,10% of the progenies and the triple resistance to PRSV-W, ZYMV and to WMV-2 was detected in 36,84%. One progeny was resistant to four viruses (PRSV-W, ZYMV, WMV-2 and CMV). The progenies were very variable on harvesting date, some being very dispersed for harvest, others with no fruits harvested before 80 days, and others presenting a highly concentrated harvest period. In comparison to the yellow casaba melon, the progenies were very late in fruit maturation, but similar for fruit weight, fruit shape, flesh thickness and internal diameter cavity. Flesh firmness varied from 7,78 N to 35,6 N, and 20% of these progenies presented the firmness superior to 20 N, very similar to cantaloupe melon type.

Progênies de melão (Cucumis melo L.) cv. Tupã, um tipo que associa as características favoráveis do fruto do melão Amarelo e do melão Cantaloupe, foram submetidas à inoculação artificial com cinco vírus [Watermerlon mosaic virus (WMV-2), Papaya ringspot virus (PRSV-w), Zucchini yelow mosaic virus (ZYMV), Squash mosaic virus (SqMV) e Cucumber mosaic virus (CMV)], em casa de vegetação. A produção e a qualidade do fruto foram avaliadas em campo. Progênies de três famílias mostraram resistência ao PRSV-w e ao ZYMV, algumas manifestaram resistência também ao WMV-2. Cerca de 63,15% apresentaram resistência somente ao PRSV-w e 52,63% somente ao ZYMV. A resistência para a combinação do PRSV-w e ZYMV ocorreu em 42,10% das progênies e a resistência tripla a PRSV-w, ZYMV e WMV-2 em 36,84%. Uma progênie foi resistente aos quatro vírus (PRSV-w, ZYMV, WMV-2 e CMV). Para o caráter concentração de colheita o comportamento das progênies foi muito variável, observando-se progênies onde a metade dos frutos foram colhidos até os 80 dias, e outras onde até os 70 dias nenhum fruto havia sido colhido. Em relação ao tipo Amarelo, foram muito tardias para a maturação dos frutos, mas mostraram semelhanças com o fruto para peso médio, formato, diâmetro interno e espessura da polpa. A firmeza da polpa variou de 7,78 N a 35,6 N, sendo que em 20% das progênies a firmeza da polpa foi superior a 20 N, muito semelhante aos melões do tipo Cantaloupe. Progenies of melon (Cucumis melo L.) cv. Tupã, that associate the favorable fruit characteristics of yellow casaba cantaloupe types, were submitted to artificial inoculation with five virus: Watermerlon mosaic virus (WMV-2), Papaya ringspot virus (PRSV-W), Zucchini yellow mosaic virus (ZYMV), Squash mosaic virus (SqMV) and Cucumber mosaic virus (CMV), in greenhouse. Yield and the fruit quality were evaluated in the field. Progenies of three families showed marked resistance to PRSV-W and to ZYMV, also some manifested resistance to WMV-2. More than 50% showed isolated resistance to PRSV-W (63,15%) and to ZYMV (52,63%). The resistance to both PRSV-W and ZYMV occurred in 42,10% of the progenies and the triple resistance to PRSV-W, ZYMV and to WMV-2 was detected in 36,84%. One progeny was resistant to four viruses (PRSV-W, ZYMV, WMV-2 and CMV). The progenies were very variable on harvesting date, some being very dispersed for harvest, others with no fruits harvested before 80 days, and others presenting a highly concentrated harvest period. In comparison to the yellow casaba melon, the progenies were very late in fruit maturation, but similar for fruit weight, fruit shape, flesh thickness and internal diameter cavity. Flesh firmness varied from 7,78 N to 35,6 N, and 20% of these progenies presented the firmness superior to 20 N, very similar to cantaloupe melon type.

The Northeastern Brazil has a great potential for production of melon ( Cucumis melo ) and watermelon ( Citrullus lanatus ). More than 20 virus species have been found naturally infecting cucurbit species around the world, but only seven of them were already found infecting those cucurbit crops in Northeastern Brazil. Plant viruses have been identified by several methods involving their morphological, physical, biological, cytological, serological and molecular properties, but serology is one of the most specific and accessible methods to obtain a rapid and precise diagnosis of a plant disease caused by virus. Several serological techniques were developed and the advent of the enzyme-linked immunosorbent assay (ELISA) has facilitated the use of serology in the identification and characterization of plant viruses, including those infecting melon and watermelon. Virus infections in melon and watermelon are considered of great importance because they can seriously affect yield all over the world, mainly in developing countries. The present review describes biological, morphological, serological and molecular properties of important virus species infecting melon and watermelon in commercial fields of Northeastern Brazil. The review covers the virus species from the following family and genera: Potyviridae genus Potyvirus : Papaya ringspot virus type Watermelon; Watermelon mosaic virus and Zucchini yellow mosaic virus ; Bromoviridae genus Cucumovirus : Cucumber mosaic virus ; Secoviridae , Subfamily: Comvirinae, genus Comovirus : Squash mosaic virus and possible viruses that cause yellowing in melon. DOI: http://dx.doi.org/10.17525/vrr.v17i1-2.60

The objective of this work was to identify new sources of simple and multiple resistances to Cowpea severe mosaic virus (CPSMV), Cowpea aphid-borne mosaic virus (CABMV) and Cucumber mosaic virus (CMV) isolates in cowpea (Vigna unguiculata). Thirty-three genotypes from the germplasm bank of Universidade Federal do Ceará were tested as to their resistance to four CPSMV isolates, two CABMV isolates and one CMV isolate. Twenty-five days after the first virus inoculations, all inoculated plants, including the asymptomatic ones, were tested by serology. Genotypes were classified as: immune, plants without symptoms and negative serology; resistant, plants with mild mosaic and positive serology; susceptible, plants with mosaic and positive serology; and highly susceptible, plants with severe mosaic, other systemic symptoms, including systemic necrosis, and positive serology. Simple and multiple resistances to viruses were identified among the evaluated genotypes, but none of them showed multiple immunities to all isolates. Four genotypes showed immunity to all CPSMV isolates, two were immune to CABMV and two showed immunity to CMV. Eleven genotypes showed multiple resistances to two viruses, allowing for the development of new cultivars with more stable and broader resistance. Genotypes Purple Knuckle Hull-55, MNC-03-731C-21 and CNCx284-66E show resistance to CABMV, even when inoculated with CMV.

The comovirus Cowpea severe mosaic virus (CPSMV) causes a disease in cowpea (Vigna unguiculata) but, despite its importance, there are no studies on the genetic diversity of viral populations. We have determined the nucleotide sequences of part of the coat protein (CP) gene of six Brazilian isolates of CPSMV. Genomic fragments (521 nucleotides) were RT-PCR amplified, cloned, and their sequences were compared with each other and with other comoviruses. Sequence comparisons indicated a high degree of conservation for the CP gene, with 92-100% nucleotide and 97-100% amino acid sequence identity among the isolates. There was no correlation between geographical origin and sequence identity or phylogeny among the isolates. Rosa F. R. Araújo Camarço [i.e. Rosa Felícia Escóssia Araújo Camarço]

Cowpea, Vigna unguiculata, can be affected by several diseases, and those caused by viruses are considered of great importance. Cowpea severe mosaic virus (CPSMV), which belongs to the family Comoviridae, genus Comovirus, stands out for its severity and degree of incidence. Its genetic variability can give rise to different strains around the world, including in Brazil. The objective of the present research was to establish a biological, serological and molecular comparison between five CPSMV isolates obtained from naturally infected plants in different States of the Northeast of Brazil. Isolates were obtained from cowpea: CPSMV-AL (State of Alagoas), CPSMV- CE (Ceara); CPSMV-MC (Piaui), CPSMV-PE (Pernambuco) and an isolate obtained from Crotalaria paulinea, in the State of Maranhao - CPSMV-CROT. A host range study evidenced biological differences among the virus isolates, especially in cowpea genotypes. The isolates were showed to be serologically and molecularly related by polymerase chain reaction �� PCR, using degenerated primers which amplified two conserved regions in the coat protein and in the replicase genes. Cloning and sequence of CPSMV-PE made possible its comparison with other CPSMV isolates and other virus species from the genus Comovirus.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:01:27Z No. of bitstreams: 1 S0103-97332009000100012.pdf: 249754 bytes, checksum: 9915c64ac233ca4a4b457907a79841a8 (MD5) Made available in DSpace on 2013-08-22T19:01:27Z (GMT). No. of bitstreams: 1 S0103-97332009000100012.pdf: 249754 bytes, checksum: 9915c64ac233ca4a4b457907a79841a8 (MD5) Previous issue date: 2009-03-01 Made available in DSpace on 2013-09-30T20:01:28Z (GMT). No. of bitstreams: 2 S0103-97332009000100012.pdf: 249754 bytes, checksum: 9915c64ac233ca4a4b457907a79841a8 (MD5) S0103-97332009000100012.pdf.txt: 27844 bytes, checksum: 42a96ad199aac25818f3619e382b2c39 (MD5) Previous issue date: 2009-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:15:44Z No. of bitstreams: 2 S0103-97332009000100012.pdf: 249754 bytes, checksum: 9915c64ac233ca4a4b457907a79841a8 (MD5) S0103-97332009000100012.pdf.txt: 27844 bytes, checksum: 42a96ad199aac25818f3619e382b2c39 (MD5) Made available in DSpace on 2014-05-20T15:15:44Z (GMT). No. of bitstreams: 2 S0103-97332009000100012.pdf: 249754 bytes, checksum: 9915c64ac233ca4a4b457907a79841a8 (MD5) S0103-97332009000100012.pdf.txt: 27844 bytes, checksum: 42a96ad199aac25818f3619e382b2c39 (MD5) Previous issue date: 2009-03-01 Pilocarpine is a natural substance with potential application in the treatment of several diseases. In this work Fourier Transform (FT)-Raman spectrum and the Fourier Transform infra red (FT-IR) spectrum of pilocarpine hydrochloride C11H17N2O2+.Cl- were investigated at 300 K. Vibrational wavenumber and wave vector have been predicted using density functional theory (B3LYP) calculations with the 6-31 G(d,p) basis set. A comparison with experiment allowed us to assign most of the normal modes of the crystal. Universidade Federal do Mato Grosso Instituto de Física Universidade Federal do Ceará (UFC) Departamento de Física Universidade Regional do Cariri Dep. Ciências Físicas e Biológicas Universidade Estadual do Ceará Universidade Federal do Ceará (UFC) Dep. Química Orgânica e Inorgânica Universidade Federal do Ceará (UFC) Departamento de Farmácia Universidade Estadual de São Paulo Faculdade de Ciências

Information about the strength of the hydrogen bond interactions in crystalline L-valine was obtained by Raman and inelastic neutron scattering spectroscopies. Raman studies were carried out from room temperature up to 423 K in order to examine both the external and the internal vibrations in L-valine. The structure seems to be stable above room temperature since no indication of a phase transition or clear indication of reorientation of L-valine molecules was observed. From the inelastic neutron scattering measurements, made between 270 and 320 K, for fully hydrogenated and partially deuterated L-valine, a better description of the low frequency modes was possible. Moreover it was possible to establish that the phase transition at low temperatures is related to the activation of an infrared mode in the Raman spectra. Additionally the low temperature phase of L-valine was further characterized by means of specific heat measurements between 5 and 350 K.

Do cruzamento entre a cultivar "sempre verde" de semente de tegumento creme e a cultivar "TVu 59", de sementes de cor marrom, selecionou-se a cultivar "Setentão". O método utilizado foi o genealógico com teste de capacidade produtiva nas gerações F3 e F4, sendo as melhores linhas submetidas a seleção massal em blocos isolados e separados por fileiras de milho na geração F5, na geração F5 foi realizada seleção individual dentro de cada linha, iniciando-se na geração F7 os ensaios de produção com 14 linhas. A seleção 010.061 (05) (01) (03) além da excelente qualidade da semente, apresenta boa capacidade produtiva, resistência ao CpSMV e CMV, respectivamente. Esta seleção agora cognominada de "Setentão" apresenta hábito de crescimento indeterminado, porte semi-ramador e boa produtividade.A cultivar of cowpea, Vigna unguiculata, named "Setentão" was obtained from a cross between "Sempre Verde" with seeds with cream integument and "TVu 59" with seeds with brown integument. The genealogical method with productive capacity test was used in the selection for F3 and F4 generations, with the best lines submitted to a bulk selection in isolated blocks (with lines separated by maige) in the F5 generation. Individual selection was carried out within each line and the assay productions with 14 lines were initiated at the F7. The selected line 010.061 (05) (01) (03) presented excellent seed quality together with good productive capacity and resistance to cowpea severe mosaic virus and cucumber mosaic virus isolated in Ceará from cowpea. The selected line named "Setentão" has indeterminate growth with semi-climbing habit and good productivity.