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This study aimed to identify by molecular analysis, morphology, chemistry and antioxidant extracts of filamentous fungi isolated from the digestive tract of Phylloicus sp, an aquatic insect that lives on leaf packages in tropical streams and participates together with fungi of the decomposition of plant substrates in aquatic habitats. Insect larvae of Phylloicus sp. were collected in streams in the state of Tocantins, Brazil. Fungi were isolated from the digestive tract of larvae after disinfection and dissection, then described and purified for identification purposes and testing for antioxidant activity. Molecular identity was performed of ITS1 and ITS4, TUB e TEF sequencing. Fungal extracts were produced in 70% ethanol solution and later lyophilized. For analysis of chemical groups of extracts, thin layer chromatography (TLC) was performed in two mobile phases and different developers. Morphology was performed by optical microscopy stained with Toluidine Blue and measurement performed using the ImageJ program. Antioxidant activity performed in TLC and by quantitative method for DPPH and hydrogen peroxide (H2O2) radicals. Four fungi were identified: Endomelanconiopsis endophytica, Myxospora musae, Neopestalotiopsis cubana and Fusarium pseudocircinatum. The TLC showed several spots with acetone/chloroform mobile phase and UV 254 nm developers and I2 vapor. Fungal extracts demonstrate antioxidant action to reduce the DPPH free radical and especially for H2O2 above 50%, E. endophytica 91.6%, M. musae 87.8%, N. cubana 89.5% and 92.3% for F. pseudocircinatum. This study demonstrated that the molecular technique by PCR was satisfactory for identifying fungi, and extracts with numerous chemical groups and potent reducing agents. Thus future work, should be carried out evaluating these four species for industrial use.

Diversidade molecular, morfológica, perfil químico qualitativo e atividade antioxidante de fungos filamentosos do trato digestivo de Phylloicus sp. (Trichoptera: Calamoceratidae). Este estudo visou identificar por análises molecular, morfológica, química e por extrato antioxidante, fungos filamentosos isolados do trato digestivo de Phylloicus sp, um inseto aquático que vive entre folhagens em riachos tropicais, e participam junto com os fungos da decomposição de substratos vegetais em habitats aquáticos. Larvas de insetos de Phylloicus sp. foram coletadas em riachos no Estado do Tocantins, Brasil. Os fungos foram isolados a partir do trato digestivo das larvas após desinfecção e dissecção, depois descritos e purificados para fins de identificação e testes para atividade antioxidante. A identidade molecular foi realizada do sequenciamento ITS1 e ITS4, TUB e TEF. Os extratos fúngicos foram produzidos em solução etanólica 70% e posterior liofilização. Para análise de grupos químicos dos extratos, foi realizada cromatografia em camada delgada (CCD) em duas fases móveis e diferentes reveladores. A morfologia foi realizada por microscopia óptica corada com Azul de Toluidina e a mensuração realizada no programa ImageJ. A atividade antioxidante realizada em CCD e por método quantitativo para os radicais DPPH e peróxido de hidrogênio (H2O2). Foram identificados quatro fungos: Endomelanconiopsis endophytica, Myxospora musae, Neopestalotiopsis cubana e Fusarium pseudocircinatum. Na CCD foi evidenciado várias manchas com fase móvel acetona/clorofórmio e reveladores UV 254 nm e vapor de I2. Os extratos fúngicos demonstram ação antioxidante para redução do radical livre DPPH e em especial para H2O2 acima de 50%, E. endophytica 91.6%, M. musae 87.8%, N. cubana 89.5% e 92.3% para F. pseudocircinatum. Este estudo demonstrou que a técnica molecular por PCR foi satisfatória para identificação dos fungos, e os extratos com inúmeros grupos químicos e potentes agentes redutores. Com isso, trabalhos futuros deverão ser realizados avaliando essas quatro espécies para uso industrial.

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This study aimed to identify by molecular analysis, morphology, chemistry and antioxidant extracts of filamentous fungi isolated from the digestive tract of Phylloicus sp, an aquatic insect that lives on leaf packages in tropical streams and participates together with fungi of the decomposition of plant substrates in aquatic habitats. Insect larvae of Phylloicus sp. were collected in streams in the state of Tocantins, Brazil. Fungi were isolated from the digestive tract of larvae after disinfection and dissection, then described and purified for identification purposes and testing for antioxidant activity. Molecular identity was performed of ITS1 and ITS4, TUB e TEF sequencing. Fungal extracts were produced in 70% ethanol solution and later lyophilized. For analysis of chemical groups of extracts, thin layer chromatography (TLC) was performed in two mobile phases and different developers. Morphology was performed by optical microscopy stained with Toluidine Blue and measurement performed using the ImageJ program. Antioxidant activity performed in TLC and by quantitative method for DPPH and hydrogen peroxide (H2O2) radicals. Four fungi were identified: Endomelanconiopsis endophytica, Myxospora musae, Neopestalotiopsis cubana and Fusarium pseudocircinatum. The TLC showed several spots with acetone/chloroform mobile phase and UV 254 nm developers and I2 vapor. Fungal extracts demonstrate antioxidant action to reduce the DPPH free radical and especially for H2O2 above 50%, E. endophytica 91.6%, M. musae 87.8%, N. cubana 89.5% and 92.3% for F. pseudocircinatum. This study demonstrated that the molecular technique by PCR was satisfactory for identifying fungi, and extracts with numerous chemical groups and potent reducing agents. Thus future work, should be carried out evaluating these four species for industrial use.

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Based on morphology, measurements of juveniles and female specimens and sequences of the D2/ D3 expansion 28S rDNA gene and ITS1 analysis by DNA barcode technique, a Xiphinema americanum group species associated with olive trees from state of Sao Paulo, Brazil was identifi ed as X. santos. This is the first report of X. santos in Southern Hemisphere and outside the European and African continents, thus extending its geographic range.

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KEY MESSAGE: Regulatory sequences from the citrus constitutive genes cyclophilin (CsCYP), glyceraldehyde-3-phosphate dehydrogenase C2 (CsGAPC2), and elongation factor 1-alpha (CsEF1) were isolated, fused to the uidA gene, and qualitatively and quantitatively evaluated in transgenic sweet orange plants. The 5' upstream region of a gene (the promoter) is the most important component for the initiation and regulation of gene transcription of both native genes and transgenes in plants. The isolation and characterization of gene regulatory sequences are essential to the development of intragenic or cisgenic genetic manipulation strategies, which imply the use of genetic material from the same species or from closely related species. We describe herein the isolation and evaluation of the promoter sequence from three constitutively expressed citrus genes: cyclophilin (CsCYP), glyceraldehyde-3-phosphate dehydrogenase C2 (CsGAPC2), and elongation factor 1-alpha (CsEF1). The functionality of the promoters was confirmed by a histochemical GUS assay in leaves, stems, and roots of stably transformed citrus plants expressing the promoter-uidA construct. Lower uidA mRNA levels were detected when the transgene was under the control of citrus promoters as compared to the expression under the control of the CaMV35S promoter. The association of the uidA gene with the citrus-derived promoters resulted in mRNA levels of up to 60-41.8% of the value obtained with the construct containing CaMV35S driving the uidA gene. Moreover, a lower inter-individual variability in transgene expression was observed amongst the different transgenic lines, where gene constructs containing citrus-derived promoters were used. In silico analysis of the citrus-derived promoter sequences revealed that their activity may be controlled by several putative cis-regulatory elements. These citrus promoters will expand the availability of regulatory sequences for driving gene expression in citrus gene-modification programs.

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Local chlorotic spots resembling early lesions characteristic of citrus leprosis (CL) were observed in leaves of two sweet orange (Citrus sinensis L.) trees in Teresina, State of Piauí, Brazil, in early 2017. However, despite the similarities, these spots were generally larger than those of a typical CL and showed rare or no necrosis symptoms. In symptomatic tissues, transmission electron microscopy revealed the presence of viroplasms in the nuclei of the infected parenchymal cells and rod-shaped particles with an average size of approximately 40 × 100 nm, resembling those typically observed during infection by dichorhaviruses. A bipartite genome of the putative novel virus, tentatively named citrus chlorotic spot virus (CiCSV) (RNA1 = 6,518 nucleotides [nt] and RNA2 = 5,987 nt), revealed the highest nucleotide sequence identity values with the dichorhaviruses coffee ringspot virus strain Lavras (73.8%), citrus leprosis virus N strain Ibi1 (58.6%), and orchid fleck virus strain So (56.9%). In addition to citrus, CiCSV was also found in local chlorotic lesions on leaves of the ornamental plant beach hibiscus (Talipariti tiliaceum (L.) Fryxell). Morphological characterization of mites recovered from the infected plants revealed at least two different types of Brevipalpus. One of them corresponds to Brevipalpus yothersi. The other is slightly different from B. yothersi mites but comprises traits that possibly place it as another species. A mix of the two mite types collected on beach hibiscus successfully transmitted CiCSV to arabidopsis plants but additional work is required to verify whether both types of flat mite may act as viral vectors. The current study reveals a newly described dichorhavirus associated with a citrus disease in the northeastern region of Brazil.

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The Camponotus Mayr genus of carpenter ants is one of the largest in species number and widely represented in the Neotropical Region. Most species are generalists and capable of exploiting diverse habitats including urban environments. Urban green areas can act as a repository of regional biodiversity, thus we investigated whether this is valid for the largest city in South America. We compared the richness of Camponotus spp. in two green areas in regions with distinct urbanization profiles and also with previous surveys made in smaller cities and in natural areas of the original Atlantic Forest. Besides the usual capture of worker specimens, we included capture of alates to improve the species richness sampling. Morphological identification of Camponotus spp. is challenging, even more when alates are included. To assist in specimen identification, we performed DNA sequencing of mitochondrial and nuclear markers. The richness observed in the less stressed urban area was higher than in the more stressed one. Camponotus spp. reported in natural areas are largely represented in the urban area. DNA sequencing for specimen identification is hampered by the lack of corresponding sequences in the GenBank, but it helped to associate workers and alates of the same species and indicated the existence of cryptic species in the genus. Capture of alates allowed detection of several species for which workers were not sampled; therefore, it is a valuable tool for surveying diversity of Camponotus or other ant taxa with arboreal or hypogeic habits.

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The occurrence of Fusarium spp associated with pecan tree (Carya illinoinensis) diseases in Brazil has been observed in recent laboratory analyses in Rio Grande do Sul State. Thus, in this study, we i) obtained Fusarium isolates from plants with disease symptoms; ii) tested the pathogenicity of these Fusarium isolates to pecan; iii) characterized and grouped Fusarium isolates that were pathogenic to the pecan tree based on morphological characteristics; iv) identified Fusarium spp to the species complex level through TEF-1α sequencing; and v) compared the identification methods used in the study. Fifteen isolates collected from the inflorescences, roots, and seeds of symptomatic plants (leaf necrosis or root rot) were used for pathogenicity tests. Morphological characterization was conducted using only pathogenic isolates, for a total of 11 isolates, based on the mycelial growth rate, sporulation, colony pigmentation, and conidial length and width variables. Pathogenic isolates were grouped based on morphological characteristics, and molecular characterization was performed by sequencing TEF-1α genes. Pathogenic isolates belonging to the Fusarium chlamydosporum species complex, Fusarium graminearum species complex, Fusarium proliferatum, and Fusarium oxysporum were identified based on the TEF-1α region. Morphological characteristics were used to effectively differentiate isolates and group the isolates according to genetic similarity, particularly conidial width, which emerged as a key morphological descriptor in this study.

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In November 2012, plants of Russell prairie gentian (Eustoma grandiflorum, Lisianthus russellianus) were collected from a commercial greenhouse in Atibaia, SP, Brazil, displaying necrotic spots on leaves and necrosis on stems, followed by generalized systemic necrosis. Disease symptom incidence was estimated at 10%. Preliminary electron microscopy observations of negatively stained leaf extracts prepared from those lesions revealed the presence of a large number of spherical tospovirus-like, approximately 100 nm in diameter. Samples of infected leaves were ground in 0.01 M phosphate buffer containing 0.5% sodium sulphide and mechanically inoculated in six plants of each species of Nicotiana glutinosa, N. tabacum cv. White Burley, N. megalosiphon, N. debneyii, Datura stramonium, Chenopodium amaranticolor, C. quinoa, and E. grandiflorum. All inoculated plants displayed local lesions 4 to 5 days after inoculation, while N. debneyii and D. stramonium showed systemic symptoms, typical of Tospovirus infection. In addition, E. grandiflorum reproduced the original symptoms. Total RNA was extracted from infected E. grandiflorum and D. stramonium, and reverse transcription (RT)-PCR was performed using universal primers BR60 and BR65 (2) targeting conserved regions of the nucleocapsid gene (N). The amplification products of approximately 450 bp were purified, cloned, and sequenced. The unknown virus was identified as Chrysanthemum stem necrosis virus (CSNV-Lis) based on host range and nucleotide sequence (Genbank Accession No. KC894721) and showed 99% identity with a CSNV chrysanthemum isolate from Japan (AB600872). Maximum likelihood phylogenetic analysis using nine homologous CSNV sequences available in GenBank classified CSNV-Lis into a monophyletic group formed by chrysanthemum isolates from Japan and China while a Japanese lisianthus isolate was separately clustered. CSNV is a member of the genus Tospovirus (Bunyaviridae) and was first reported on chrysanthemum in Brazil (1) and later in the Netherlands, Slovenia, United Kingdom, and Japan (3). Despite scattered recent reports of CSNV, the simultaneous production of chrysanthemum and lisianthus crops along the year by Brazilian farmers has contributed to the virus maintenance in the field. The high identity between Brazilian and Japanese isolates of CSNV suggest a possible reintroduction of the virus through exchange of vegetative propagating material. References: (1) L. M. L. Duarte et al. J. Phytopathol. 143:569, 1995. (2) M. Eiras et al. Fitopatol. Bras. 26:170, 2001. (3) K. Momonoi et al. J. Gen. Plant Pathol. 77:142, 2011.

RESUMO

Zamioculcas zamiifolia (Lodd.) Engl. ("Zanzibar Gem," "ZZ plant") is the monotypic species of the genus belonging to the family Araceae. It is a stemless perennial plant native to Africa, from Kenya to South Africa, that produces succulent rhizomes at the base of its attractive dark green and glossy foliage. Symptoms of mosaic and foliar distortion were observed on a plant purchased at an ornamental plants shop in São Paulo state, Brazil. In order to identify the causal agent, transmission and serological tests, as well as electron microscopy (EM) observations, reverse transcription (RT)-PCR, and sequencing were carried out. EM observations revealed the presence of elongated, flexuous viral particles in foliar extracts and cytoplasmic lamellar aggregates of type II lamellar inclusions (Edwardson's classification), in thin sections. No symptoms were induced following mechanical inoculation on Chenopodium amaranticolor, C. murale, Gomphrena globosa, Nicotiana megalosiphon, N. debneyii, nor on the aroids Philodendron scandens, P. selloum, Dieffenbachia amoena, Colocasia esculenta, and Z. zamiifolia. Up to 2 months after inoculation, plants were still symptomless, and the virus was not detected by RT-PCR. The indirect ELISA tests were negative with antisera against Dasheen mosaic virus (gift from F. W. Zettler, University of Florida) and Turnip mosaic virus (gift from P. Roggero, IFA, Turin, Italy). RT-PCR performed on the original purchased ornamental plant with potyvirus-specific primers (CI-R = ACICCRTTYTCDATDATRTTIGTIGC and CI-F = GGIVVIGTIGGIWSIGGIAARTCIAC) targeting the cytoplasmic inclusion protein cistron of the potyvirus genome produced a fragment of approximately 650 bp (GenBank Accession No. KC990386). The sequence was similar to those of potyvirus species with nucleotide identity, determined by PAUP v.4.0b10 for Macintosh, ranging from 64% for Pokeweed mosaic virus (JQ609065) to 93% for Konjac mosaic virus KoMV-F (NC007913). KoMV has been detected in aroid species in Taiwan, India, Korea, Japan (1,2), Germany, and The Netherlands (3,4). This is the first report of a viral disease on Z. zamiifolia and of KoMV in the Americas. Such information along with the vegetative propagation of ZZ plants strongly suggests that KoMV is spread worldwide. References: (1) P. Manikonda et al. J. Phytopathol. 159:133, 2011. (2) M. Nishiguchi et al. Arch Virol. 151:1643, 2006. (3) D.-E. Lesemann and S. Winter. Acta Hort. 568:135, 2002. (4) K. Pham et al. Acta Hort. 568:143, 2002.

RESUMO

Ants are found worldwide playing an important environmental role. Some species are considered as agricultural pests and potential risk to human life and public health acting as pathogens carriers. Ants as Paratrechina longicornis and Camponotus spp. have been found inside hospitals. The aim of this study was the research of mycobacteria in 138 samples of ants (137 Paratrechina longicornis and only one Camponotus spp.) which got into the laboratories of tuberculosis diagnosis. These ants were suspended in sterile saline solution and inoculated into Petragnani and Stonebrink media, incubated at 37° C until 90 days and the isolates were identified as environmental mycobacteria (1 Mycobacterium fortuitum peregrinum, 1 Mycobacterium smegmatis) and 1 Mycobacterium tuberculosis complex. These results showed that ants should also act as mechanical vectors of mycobacteria dissemination in risk environments, reinforcing their significance in public health.

As formigas têm uma distribuição mundial e representam importante papel no ecossistema. Algumas espécies são consideradas pragas para a agricultura e um risco potencial à vida humana e à saúde pública veiculando mecanicamente agentes patogênicos. Formigas como Paratrechina longicornis e Camponotus spp. têm sido encontradas em ambientes hospitalares. O foco do presente estudo foi a identificação de micobactérias em 138 amostras de formigas (137 Paratrechina longicornis e apenas uma Camponotus sp.), que tiveram acesso a áreas de laboratórios de diagnóstico de tuberculose. Essas formigas foram suspensas em solução salina estéril que foi semeada em meios de Petragnani e Stonebrink, incubadas a 37º C por até 90 dias e as estirpes de micobactérias isoladas foram identificadas pelas técnicas clássicas como micobactérias ambientais (sendo 1 Mycobacterium smegmatis, 2 Mycobacterium fortuitum peregrinum e 1 Mycobacterium tuberculosis). Esses resultados mostram que as formigas podem também se constituir vetores de dispersão de micobactérias em ambientes de risco, reforçando sua importância em saúde pública.

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RESUMO

ABSTRACT Ants are found worldwide playing an important environmental role. Some species are considered as agricultural pests and potential risk to human life and public health acting as pathogens carriers. Ants as Paratrechina longicornis and Camponotus spp. have been found inside hospitals. The aim of this study was the research of mycobacteria in 138 samples of ants (137 Paratrechina longicornis and only one Camponotus spp.) which got into the laboratories of tuberculosis diagnosis. These ants were suspended in sterile saline solution and inoculated into Petragnani and Stonebrink media, incubated at 37° C until 90 days and the isolates were identified as environmental mycobacteria (1 Mycobacterium fortuitum peregrinum, 1 Mycobacterium smegmatis) and 1 Mycobacterium tuberculosis complex. These results showed that ants should also act as mechanical vectors of mycobacteria dissemination in risk environments, reinforcing their significance in public health.

RESUMO As formigas têm uma distribuição mundial e representam importante papel no ecossistema. Algumas espécies são consideradas pragas para a agricultura e um risco potencial à vida humana e à saúde pública veiculando mecanicamente agentes patogênicos. Formigas como Paratrechina longicornis e Camponotus spp. têm sido encontradas em ambientes hospitalares. O foco do presente estudo foi a identificação de micobactérias em 138 amostras de formigas (137 Paratrechina longicornis e apenas uma Camponotus sp.), que tiveram acesso a áreas de laboratórios de diagnóstico de tuberculose. Essas formigas foram suspensas em solução salina estéril que foi semeada em meios de Petragnani e Stonebrink, incubadas a 37º C por até 90 dias e as estirpes de micobactérias isoladas foram identificadas pelas técnicas clássicas como micobactérias ambientais (sendo 1 Mycobacterium smegmatis, 2 Mycobacterium fortuitum peregrinum e 1 Mycobacterium tuberculosis). Esses resultados mostram que as formigas podem também se constituir vetores de dispersão de micobactérias em ambientes de risco, reforçando sua importância em saúde pública.

RESUMO

The objectives of the present study were the subtyping of Campylobacter jejuni subsp. jejuni strains obtained from humans and different animal species using PCR-RFLP, and the detection, by means of the same technique, of strains related to serotype PEN O19:LIO 7, the main C. jejuni serotype linked to Guillain-Barré Syndrome (GBS). Seventy C. jejuni strains isolated from human feces (n=33), primates (n=15), dogs (n=5), swine (n=2), bovines (n=1), abortion material from goats (n=2) and poultry carcasses (n=12), all collected in the state of São Paulo, were subtyped by means of PCR-RFLP of fla A gene, using restriction endonucleases Hae III, Afa I and Mbo I. Seven subtypes were observed when using the enzyme Hae III; eight when using Mbo I; and seven when using Afa I. The combination of the three endonucleases led to 16 fla-RFLP subtypes, from which ten subtypes shared strains of human and animal origin. From these, seven subtypes were observed in human and broiler strains. In eight subtypes, the other animal species shared patterns with human strains. It was inferred that, besides broilers, swine, goats, dogs and primates may be sources of infection for human in São Paulo. PCR-RFLP is a highly discriminatory technique that may be applied to molecular epidemiology studies of samples from different origins. Besides, the study also enabled the detection of two human strains and two primate strains related to serotype PEN O19: LIO 7.

Assuntos

RESUMO

The objectives of the present study were the subtyping of Campylobacter jejuni subsp. jejuni strains obtained from humans and different animal species using PCR-RFLP, and the detection, by means of the same technique, of strains related to serotype PEN O19:LIO 7, the main C. jejuni serotype linked to Guillain-Barré Syndrome (GBS). Seventy C. jejuni strains isolated from human feces (n=33), primates (n=15), dogs (n=5), swine (n=2), bovines (n=1), abortion material from goats (n=2) and poultry carcasses (n=12), all collected in the state of São Paulo, were subtyped by means of PCR-RFLP of fla A gene, using restriction endonucleases Hae III, Afa I and Mbo I. Seven subtypes were observed when using the enzyme Hae III; eight when using Mbo I; and seven when using Afa I. The combination of the three endonucleases led to 16 fla-RFLP subtypes, from which ten subtypes shared strains of human and animal origin. From these, seven subtypes were observed in human and broiler strains. In eight subtypes, the other animal species shared patterns with human strains. It was inferred that, besides broilers, swine, goats, dogs and primates may be sources of infection for human in São Paulo. PCR-RFLP is a highly discriminatory technique that may be applied to molecular epidemiology studies of samples from different origins. Besides, the study also enabled the detection of two human strains and two primate strains related to serotype PEN O19: LIO 7.

RESUMO

The objectives of the present study were the subtyping of Campylobacter jejuni subsp. jejuni strains obtained from humans and different animal species using PCR-RFLP, and the detection, by means of the same technique, of strains related to serotype PEN O19:LIO 7, the main C. jejuni serotype linked to Guillain-Barré Syndrome (GBS). Seventy C. jejuni strains isolated from human feces (n=33), primates (n=15), dogs (n=5), swine (n=2), bovines (n=1), abortion material from goats (n=2) and poultry carcasses (n=12), all collected in the state of São Paulo, were subtyped by means of PCR-RFLP of fla A gene, using restriction endonucleases Hae III, Afa I and Mbo I. Seven subtypes were observed when using the enzyme Hae III; eight when using Mbo I; and seven when using Afa I. The combination of the three endonucleases led to 16 fla-RFLP subtypes, from which ten subtypes shared strains of human and animal origin. From these, seven subtypes were observed in human and broiler strains. In eight subtypes, the other animal species shared patterns with human strains. It was inferred that, besides broilers, swine, goats, dogs and primates may be sources of infection for human in São Paulo. PCR-RFLP is a highly discriminatory technique that may be applied to molecular epidemiology studies of samples from different origins. Besides, the study also enabled the detection of two human strains and two primate strains related to serotype PEN O19: LIO 7.

RESUMO

ABSTRACT The virulence of four entomopathogenic nematodes strains against Bradysia mabiusi (Lane) 3º 4º instar larvae in laboratory conditions and the persistence of Heterorhabditis indica Poinar et al. 1992 on organic substrates, in the greenhouse, were evaluated. For the virulence test, four nematodes strains were used: Heterorhabditis indica IBCB-n05, Heterorhabditis sp. IBCB-n10, Steinernema glaseri CCA and S. carpocapsae CCA. These nematodes were evaluated at the dosage of 200 infective juveniles (IJ)/ larvae. For the persistence study, the nematode H. indica was selected and two tests were carried out. In the first test, the nematode was applied at the dosages of 5.7 and 22.6 IJ/cm2, and in the second, at the dosages of 10 and 50 IJ/cm2. For both tests, two evaluations were done, releasing insect larvae on the treated and nontreated substrate at 24 hours and 15 days after the application. The nematode H. indica IBCB-n05 was the most virulent, causing 100% mortality of larvae, but did not differ statistically from Heterorhabditis sp. IBCB-n10 and S. carpocapsae(96% and 83% mortality, respectively). For the first persistence test, H. indica IBCB-n05 at the dosages of 5.7 and 22.6 IJ/cm2 afforded, respectively, 67 and 80% mortality of larva (corrected by Abotts formula) 24 hours after the application. For the other persistence test, the nematode at the dosages of 10 and 50 IJ/cm2 afforded, respectively, 69 and 97% mortality (corrected by Abotts formula) 24 hs after application. The persistence of the neiological control, Sciaridae, Steinernema sp., Heterorhabditis sp., Bradysia mabiusi.

RESUMO Foi avaliada, em condições de laboratório, a virulência de quatro isolados de nematóides entomopatogênicos contra larvas de 3º e 4º instares de Bradysia mabiusi Lane, e a persistência de Heterorhabditis indica Poinar et al. 1992 em substratos orgânicos, dentro de casa de vegetação. No teste de virulência, foram avaliados os isolados H. indica IBCB-n05, Heterorhabditis sp. IBCB-n10, Steinernema glaseri CCA e S. carpocapsae CCA. Os nematóides foram usados na dosagem de 200 juvenis infectivos (JI)/larva. Para a avaliação de persistência, foi selecionado o nematóide H. indica IBCB-n05, sendo realizados 2 testes em casa de vegetação. Em um teste, o nematóide foi aplicado nas dosagens de 5,7 e 22,6 JI/cm2 e, em outro, nas dosagens de 10 e 50 JI/cm2. Nos dois testes, foram feitas duas avaliações, liberando-se larvas do inseto nas amostras tratadas do substrato após 24 horas e 15 dias da aplicação. O nematóide H. indica IBCB-n05 provocou 100% de mortalidade dos insetos, mas não diferiu significativamente do Heterorhabditis sp. IBCB-n10 e S. carpocapsae (96% e 83% de mortalidade, respectivamente). No estudo de persistência, o nematóide H. indica, nas dosagens de 5,7 e 22,6 JI/cm2, proporcionou, respectivamente, 67 e 80% de mortalidade corrigida das larvas (formula de Abott) após 24 horas da aplicação. Em outro teste, o nematóide, nas dosagens de 10 e 50 JI/cm2, proporcionou, respectivamente, 69% e 97% de mortalidade corrigida após 24 horas da aplicação. A persistência do nematóide nos testes em casa de vegetação foi bastante afetada já que a mortalidade do inseto, 15 dias após a aplicação, não passou de 15%.

RESUMO

Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in accidental hosts, including humans. Complete genome sequencing of Leptospira interrogans serovar Copenhageni and comparative analysis with the available Leptospira interrogans serovar Lai genome reveal that despite overall genetic similarity there are significant structural differences, including a large chromosomal inversion and extensive variation in the number and distribution of insertion sequence elements. Genome sequence analysis elucidates many of the novel aspects of leptospiral physiology relating to energy metabolism, oxygen tolerance, two-component signal transduction systems, and mechanisms of pathogenesis. A broad array of transcriptional regulation proteins and two new families of afimbrial adhesins which contribute to host tissue colonization in the early steps of infection were identified. Differences in genes involved in the biosynthesis of lipopolysaccharide O side chains between the Copenhageni and Lai serovars were identified, offering an important starting point for the elucidation of the organism's complex polysaccharide surface antigens. Differences in adhesins and in lipopolysaccharide might be associated with the adaptation of serovars Copenhageni and Lai to different animal hosts. Hundreds of genes encoding surface-exposed lipoproteins and transmembrane outer membrane proteins were identified as candidates for development of vaccines for the prevention of leptospirosis.

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Xylella fastidiosa is a xylem-dwelling, insect-transmitted, gamma-proteobacterium that causes diseases in many plants, including grapevine, citrus, periwinkle, almond, oleander, and coffee. X. fastidiosa has an unusually broad host range, has an extensive geographical distribution throughout the American continent, and induces diverse disease phenotypes. Previous molecular analyses indicated three distinct groups of X. fastidiosa isolates that were expected to be genetically divergent. Here we report the genome sequence of X. fastidiosa (Temecula strain), isolated from a naturally infected grapevine with Pierce's disease (PD) in a wine-grape-growing region of California. Comparative analyses with a previously sequenced X. fastidiosa strain responsible for citrus variegated chlorosis (CVC) revealed that 98% of the PD X. fastidiosa Temecula genes are shared with the CVC X. fastidiosa strain 9a5c genes. Furthermore, the average amino acid identity of the open reading frames in the strains is 95.7%. Genomic differences are limited to phage-associated chromosomal rearrangements and deletions that also account for the strain-specific genes present in each genome. Genomic islands, one in each genome, were identified, and their presence in other X. fastidiosa strains was analyzed. We conclude that these two organisms have identical metabolic functions and are likely to use a common set of genes in plant colonization and pathogenesis, permitting convergence of functional genomic strategies.

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