56 research outputs found

    Descricao fenotipica de um pomar pioneiro de goiabeira serrana

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    Trabalho de Conclusão de Curso - Universidade Federal de Santa Catarina. Curso de Agronomia

    ESTUDO DAS INTERAÇÕES ENTRE PROTOZOÁRIOS CILIADOS DE VIDA LIVRE E SALMONELLA TYPHIMURIUM

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    Bactérias endofíticas associadas à cultura de tecidos e às folhas de Plinia peruviana

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    The objective of this work was to isolate endophytic bacteria from tissue culture and leaves of jaboticaba (Plinia peruviana) and to evaluate their potential as plant growth-promoting bacteria. The bacteria were isolated from nodal segments grown in vitro and from leaves from a tree under natural conditions, totaling 11 and 54 isolates, respectively. The isolates were characterized by colony morphology. The indolic compounds produced by the isolates, in the presence or absence of 100 mg L-1 tryptophan, were quantified. The greatest producers of these compounds were identified by sequencing the 16S rRNA gene and were inoculated on jaboticaba seeds, using Azospirillum brasilense (Ab-V6) as a positive control. The sensitivity of bacteria to eight antibiotics was also evaluated. All assessed bacteria produced indolic compounds, especially Bacillus sp., with a content of 27.41 µg mL-1. The germination rate of the seeds inoculated with Stenotrophomonas sp. was high – 97.34% compared with that of 74.67% of the negative control. Bacillus sp. and Stenotrophomonas sp. also sped up germination. Chloramphenicol limited the growth of 82% of the isolates, followed by amoxicillin, gentamicin, levofloxacin, and tetracycline, which limited 70%; erythromycin was only effective against 35%. The endophytic bacteria isolated from jaboticaba show characteristics of plant growth-promoting bacteria, and Bacillus sp. and Stenotrophomonas sp., obtained from tissue culture, are capable of enhancing jaboticaba seed germination.O objetivo deste trabalho foi isolar bactérias endofíticas de cultura de tecidos e de folhas de jabuticabeira (Plinia peruviana) e avaliar seu potencial como bactérias promotoras de crescimento de plantas. As bactérias foram isoladas a partir de segmentos nodais cultivados in vitro e de folhas de árvore sob condições naturais, tendo totalizado 11 e 54 isolados, respectivamente. Os isolados foram caracterizados pela morfologia da colônia. Foram quantificados os compostos indólicos produzidos pelos isolados, na presença ou na ausência de 100 mg L-1 de triptofano. Os maiores produtores destes compostos foram identificados pelo sequenciamento do gene 16S rRNA e foram inoculados em sementes de jabuticaba, tendo-se utilizado Azospirillum brasilense (Ab-V6) como controle positivo. Também avaliou-se a sensibilidade das bactérias a oito antibióticos. Todas as bactérias avaliadas produziram compostos indólicos, especialmente Bacillus sp., com quantidade de 27,41 µg mL-1. A taxa de germinação das sementes inoculadas com Stenotrophomonas sp. foi elevada – 97,34% em comparação à de 74,67% do controle negativo. Bacillus sp. e Stenotrophomonas sp. também aumentaram a velocidade de germinação. O cloranfenicol limitou o crescimento de 82% dos isolados, seguido pelas amoxicilina, gentamicina, levofloxacina e tetraciclina, que limitaram 70%; a eritromicina foi eficaz apenas contra 35%. As bactérias endofíticas isoladas da jabuticaba apresentam características de bactérias promotoras de crescimento de plantas, e Bacillus sp. e Stenotrophomonas sp., provenientes da cultura de tecido, são capazes de aprimorar a germinação de sementes de jabuticaba

    Highly scab-resistant transgenic apple lines achieved by introgression of HcrVf2 controlled by different native promoter lengths

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    Apple scab, caused by the ascomycete Venturia inaequalis, is the most damaging fungal disease of commercial apple orchards. Functional scab resistance genes are present in some wild Malus species. The HcrVf2 gene, derived from the Vf-region of the wild apple Malus floribunda 821 and encoding a receptor-like protein, has proved to confer scab resistance in a transgenic susceptible cultivar. In order to minimize nonplant DNA in genetically modified apple and to go a step toward the development of cisgenic apples, we have studied the capability of the HcrVf2 gene to confer apple scab resistance when it is controlled by its own promoter. Three promoter deletion constructs containing 115, 288, and 779bp of the 5′ untranslated region and the HcrVf2 gene were used to transform the scab susceptible apple cvs. ‘Gala' and ‘Elstar.' The influence of the promoter length on both the HcrVf2 expression level and the response to V. inaequalis was analyzed in different transgenic lines. Promoter length was found to influence both the constitutive transcription levels of HcrVf2 in transgenic lines and the resistance level. Highly scab resistant ‘Elstar' and ‘Gala' plants were obtained, proving that the HcrVf2 gene controlled by its native promoter is effective in conferring resistance to V. inaequalis similarly as Vf introgressed in apple cvs. through classical breedin

    Bactérias endofíticas promotoras de crescimento de plantas em mudas de pupunheira

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    The objective of this work was to isolate endophytic bacteria from peach palm (Bactris gasipaes var. gasipaes) plants and to evaluate the effects of their inoculation on the plant seedlings. Bacteria were isolated from the leaves and roots of the seedlings and from the meristems of peach palm plants in vitro. The isolates were characterized phenotypically and, then, 15 of them, representing different phenotypic groups, were selected and identified by partial sequencing of the 16S rRNA gene. Afterward, these isolates and two commercial strains of Azospirillum brasilense (Ab-V5 and Ab-V6) were inoculated in the peach palm seedlings. After 76 days, the seedlings were evaluated for plant development. The following six genera were identified based on the sequencing: Pseudomonas, Enterobacter, Rhizobium, Stenotrophomonas, Klebsiella, and Erwinia. Out of the 15 inoculated isolates, 9 had a positive effect on the root dry mass of palm peach, with CNPF 77 (Enterobacter sp.), CNPF 100 (Rhizobium sp.), and CNP 179 and CNPF 277 (Stenotrophomonas sp.) standing out. Peach palm seedlings harbor endophytic bacteria which are able to increase root dry matter.O objetivo deste trabalho foi isolar bactérias endofíticas de pupunheira (Bactris gasipaes var. gasipaes) e avaliar os efeitos da inoculação delas em mudas da planta. As bactérias foram isoladas de folhas e raízes das mudas e de meristemas de pupunheira in vitro. Os isolados foram caracterizados fenotipicamente, e, depois, 15 deles, representando grupos fenotípicos distintos, foram selecionados e identificados por meio do sequenciamento parcial do gene 16S rRNA. Em seguida, esses isolados e duas estirpes comerciais de Azospirillum brasilense (Ab-V5 e Ab-V6) foram inoculados em plântulas de pupunheira. Após 76 dias, as mudas foram avaliadas quanto ao desenvolvimento vegetal. Foram identificados os seis seguintes gêneros com base no sequenciamento: Pseudomonas, Enterobacter, Rhizobium, Stenotrophomonas, Klebsiella e Erwinia. Dos 15 isolados inoculados, 9 tiveram efeito positivo sobre a massa de matéria seca de raízes, com destaque para CNPF 77 (Enterobacter sp.), CNPF 100 (Rhizobium sp.), e CNP 179 e CNPF 277 (Stenotrophomonas sp.). Mudas de pupunheira abrigam bactérias endofíticas capazes de aumentar a matéria seca das raízes

    Bacillus megaterium: bacteria endofítica de callos de Ilex paraguariensis con actividad de promoción del crecimiento

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    Los microorganismos endófitos viven dentro de plantas sanas y su aislamiento e identificación pueden favorecer las aplicaciones biotecnológicas. Los microorganismos endofíticos fueron encontrados en callos de Ilex paraguariensis cultivados in vitro durante cinco meses. Se usó la secuenciación de la región 16S rRNA para identificar dos aislados como Bacillus megaterium. La presencia de células bacterianas en los espacios intercelulares de los cultivos de callos se detectó mediante análisis ultraestructurales. Los aislamientos también se evaluaron para la producción de ácido indol acético (AIA) y su potencial en la promoción del crecimiento de las plántulas de Phaseolus vulgaris L. La síntesis de ácido AIA en presencia y ausencia de L-triptófano se detectó por análisis colorimétrico para ambos aislamientos. En presencia de extractos de las cepas IPC06 e IPC07, las plántulas de P. vulgaris crecieron más rápido en comparación con las plantas control sin el extracto en pruebas in vitro.Palabras clave: yerba mate, 16S rRNA, secuenciación, cultivo de tejido

    Salmonella enterica em água de dessedentação animal

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    INDIRECT ORGANOGENESIS FROM LEAF EXPLANTS AND IN VITRO SHOOTS LTIPLICATION OF Eucalyptus benthamii X Eucalyptus dunnii

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    Os objetivos deste trabalho foram avaliar diferentes meios de cultura na organog\ueanese indireta e na multiplica\ue7\ue3o in vitro de brotos de Eucalyptus benthamii x Eucalyptus dunnii . Para organog\ueanese, explantes foliares foram excisados no sentido transversal e cultivados in vitro, sendo os seguintes fatores testados: dois meios de cultura (MS N/2 e JADS) adicionados de 0,1 \u3bcM de ANA, duas concentra\ue7\uf5es de thidiazuron (0,1 e 0,5 \u3bcM) e presen\ue7a ou n\ue3o de PVP-40 (250 mg L-1). Ap\uf3s 70 dias de cultivo foram avaliadas as porcentagens de explantes oxidados totalmente, formando calo, produzindo antocianina, formando gema, formando brota\ue7\uf5es e o n\ufamero de brota\ue7\uf5es formadas por explante regenerando. No experimento de multiplica\ue7\ue3o, brota\ue7\uf5es isoladas foram cultivadas em meio MS, JADS e WPM, adicionados de 1,11 \u3bcM de BAP. Foram realizados quatro subcultivos a cada 28 dias e em cada subcultivo foram avaliados: a porcentagem de oxida\ue7\ue3o, de explantes apresentando clorose total ou parcial, massa fresca e n\ufamero m\ue9dio de brotos por explante. O meio de cultura MS N/2 suplementado com 0,1 \u3bcM de ANA, 0,5 \u3bcM de TDZ e PVP-40 promoveu a maior taxa de organog\ueanese (8,3%). No meio de cultura MS com 1,11 \u3bcM de BAP, a taxa de multiplica\ue7\ue3o foi maior que nos outros meios, no primeiro e segundo subcultivos (9,28 e 9,24 por m\ueas), n\ue3o havendo diferen\ue7a entre os tr\ueas meios nos demais subcultivos.The aims of this research were to evaluate different culture media for indirect organogenesis and shoot multiplication of Eucalyptus benthamii x Eucalyptus dunnii . For organogenesis, leaf explants were used to test the following treatments: two culture media (MS N/2 and JADS) supplemented with 0.1 \u3bcM 1-naphthaleneacetic acid (NAA) and thidiazuron (TDZ) (0.1 or 0.5 \u3bcM), with or without PVP- 40 (250 mg L-1). The percentage of oxidized explants, callus forming explants, explants with anthocyanin, buds, shoots and the shoot number per explant were evaluated. In the multiplication experiment, isolated shoots were cultivated in MS, JADS and WPM media, all supplemented with 1.11 \u3bcM BAP. Four subcultures were carried out every 28 days. In every subculture the explant oxidation, partial or total leaf chlorosis, fresh mass and mean number of shoot per explant were evaluated. The MS N/2 medium supplemented with 0.1 \u3bcM NAA and 0.5 \u3bcM TDZ promoted the highest rate of organogenesis (8.3%) and the culture media MS supplemented with 1.11 \u3bcM BAP the multiplication rate was higher than in the other media, in the first and the second subcultures (9.28 and 9.24, respectively), without differences between the three media in the following subcultures
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