scholarly journals Avaliação de bactérias endofíticas para o controle biológico da mancha foliar de Exserohilum turcicum em milho

2015 ◽  
Vol 82 (0) ◽  
Author(s):  
Humberto Franco Shiomi ◽  
Itamar Soares de Melo ◽  
Marli Teixeira de Almeida Minhoni
Keyword(s):  
Bacillus Subtilis ◽  
Exserohilum Turcicum ◽  
Xanthomonas Axonopodis ◽  
Streptomyces Sp ◽  
Bacillus Agaradhaerens

RESUMO:A eficácia de nove isolados de bactérias endofíticas foi avaliada no biocontrole da mancha foliar de Exserohilum turcicum, pela microbiolização das sementes e da parte aérea do milho híbrido AS-1548 (72 e 24 horas antes e no mesmo dia da inocula ção do patógeno) em condições de casa de vegetação. Verificou-se que Bacillus subtilis 0G, Bacillus lentimorbus, Streptomyces sp. e Bacillus agaradhaerens se destacaram dos demais, quando aplicados na parte aérea, em todos os intervalos testados, com um controle na ordem de 42 a 61%. Quando as bactérias foram aplicadas nas sementes, Bacillus lentimorbus, Streptomyces sp., Ewingella ameri cana e Xanthomonas axonopodis foram os mais eficientes, com um controle entre 37 e 59%.

scholarly journals SELEÇÃO DE BACTÉRIAS ENDOFÍTICAS COM AÇÃO ANTAGÔNICA A FITOPATÓGENOS

2008 ◽  
Vol 9 (4) ◽  
pp. 535 ◽  
Author(s):  
Humberto Franco SHIOMI ◽  
Itamar Soares de MELO ◽  
Marli Teixeira de Almeida MINHONI
Keyword(s):  
Bacillus Subtilis ◽  
Rhizoctonia Solani ◽  
Fusarium Moniliforme ◽  
Sclerotium Rolfsii ◽  
Pythium Aphanidermatum ◽  
Exserohilum Turcicum ◽  
Streptomyces Sp ◽  
Bacillus Agaradhaerens

Muitos métodos rápidos e eficientes de seleção de agentes de biocontrole de fitopatógenos tem sido utilizados, visando reduzir tempo e custo dispendido em testes de campo. Neste trabalho realizou-se uma seleção de isolados endofíticos com potencial de uso no biocontrole de fitopatógenos em testes de antagonismo in vitro. De um total de 95 isolados de bactérias endofíticas do milho, seis foram selecionados quanto à inibição a Pythium aphanidermatum. A essa seleção, foram incluídos um isolado de Bacillus subtilis 0G, Bacillus lentimorbus e Streptomyces sp., para verificação de antagonismo a Rhizoctonia solani, Fusarium moniliforme, Sclerotium rolfsii e Exserohilum turcicum. Verificou-se que os endofíticos B. subtilis 0G, B. lentimorbus e Streptomyces sp., apresentaram ação antagônica superior aos demais, com taxas de inibição entre 32,0% e 53,8%. Dentre os endofíticos do milho, Bacillus agaradhaerens foi o que mais se destacou, com taxas de inibição variando entre 43,7% e 52,3% e indicando uma inespecificidade de ação. Este estudo, embora preliminar, permite vislumbrar a utilização desses endofíticos na supressão de doenças em diferentes sistemas patógeno-hospedeiro em testes subseqüentes, sob condições de casa-de-vegetação e a campo.

scholarly journals Bakteri Agens Hayati Potensial terhadap Patogen Penting pada Padi

2020 ◽  
Vol 16 (1) ◽  
pp. 37-48
Author(s):  
Ratna Sari Dewi ◽  
Giyanto Giyanto ◽  
Meity Suradji Sinaga ◽  
Dadang Dadang ◽  
Bambang Nuryanto
Keyword(s):  
Bacillus Subtilis ◽  
Rhizoctonia Solani ◽  
Pseudomonas Fluorescens ◽  
Pyricularia Oryzae ◽  
Burkholderia Glumae ◽  
Streptomyces Sp ◽  
Ralstonia Pickettii

Saat ini teknologi pengendalian hayati penyakit utama padi terus berkembang. Dalam pengembangan teknologi pengendalian hayati, mekanisme penghambatan patogen dalam perkembangan penyakit pada suatu populasi tumbuhan dalam area tertentu menjadi hal yang penting. Penelitian bertujuan mendapatkan bakteri agens hayati potensial dalam pengendalian penyakit penting padi di antaranya yang disebabkan Pyricularia oryzae, Xanthomnas oryzae pv. oryzae, Rhizoctonia solani, Burkholderia glumae, dan Drechlera oryzae, berdasarkan mekanisme antagonisme, kemampuan menginduksi ketahanan dan mendukung kebugaran tanaman, serta kompatibilitas antaragens hayati. Ralstonia pickettii TT47, Pseudomonas fluorescens P12, Chromobacterium sp. T51118, Bacillus subtilis 451 dan 154, serta Streptomyces sp. T51105 dibuktikan memiliki mekanisme antibiosis dengan menghasilkan metabolit sekunder dan senyawa volatil. Berdasarkan uji produksi enzim kitinolitik Chromobacterium sp. dan Streptomyces sp. memiliki mekanisme lisis. Aktivitas antibiotik R. pickettii dan P. fluorescens tergolong kuat terhadap P. oryzae dengan penekanan secara berurutan sebesar 79.68% dan 77.59% pada uji biakan ganda. Penekanan pertumbuhan miselium P. oryzae dan R. solani pada uji volatil mencapai 100% oleh Chromobacterium sp. Semua agens hayati umumnya mampu menginduksi ketahanan dan mendukung kebugaran tanaman. Uji kompatibilitas menunjukan R. pickettii, P. fluorescens, dan Chromobacterium sp. bersifat kompatibel. Dari hasil penelitian diperoleh tiga bakteri agens hayati dengan kategori unggul, yaitu P. fluorescens P12, R. pickettii TT47, dan Chromobacterium sp. T51118. Ketiganya mampu menekan pertumbuhan patogen, menginduksi ketahanan dan mendukung kebugaran tanaman, memiliki patogen sasaran yang lebih beragam, serta bersifat kompatibel.

scholarly journals Biodegradation of Vulcanized SBR: A Comparison between Bacillus subtilis, Pseudomonas aeruginosa and Streptomyces sp

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mostafa Galal Aboelkheir ◽  
Priscilla Braga Bedor ◽  
Selma Gomes Leite ◽  
Kaushik Pal ◽  
Romildo Dias Toledo Filho ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Contact Angle ◽  
Bacillus Subtilis ◽  
Polymeric Chain ◽  
Bacterial Strains ◽  
Carbon Loss ◽  
Streptomyces Sp ◽  
Vulcanized Rubber ◽  
Recycling Technique ◽  
Biological Recycling

AbstractRubber residues present harmful impacts on health and environment, besides wasting valuable and huge amounts of rubber. Biological recycling technique is focused here to minimize this problem. A comparison of the biodegradation effect caused by Bacillus subtilis, Pseudomonas aeruginosa, and Streptomyces sp., separately, on vulcanized SBR-rubber during 4 weeks is reported. The surface and molecular analyses were studied by FTIR-ATR, TGA, DSC, TC and SEM/EDS, in addition to the contact angle and crosslinking tests. B. subtilis, P. aeruginosa, and Streptomyces sp. evoked after 4 weeks a loss in v-SBR crosslinks by 17.15, 10.68 and 43.39% and also in the contact angle with water by 14.10, 12.86 and 15.71%, respectively., if compared to Control samples. FTIR findings indicate that the polymeric chain has been partially consumed causing C-C bonds scission indicating the biodegradation and bio-devulcanization phenomena. The bacterial strains caused a carbon loss by 9.15, 5.97 and 4.55% after one week and 16.09, 16.79 and 18.13% after four weeks for B. subtilis, P. aeruginosa, and Streptomyces sp. mediums, respectively. DSC and EDS results are also promising and highlighting Streptomyces sp. strain as the most effective biodegradative one as an alternative and natural mean of degrading vulcanized rubber residues.

scholarly journals Effect of various biological control agents (BCAs) on drought resistance and spring barley productivity

2020 ◽  
Vol 17 ◽  
pp. 00063
Author(s):  
Radik Safin ◽  
Lilia Karimova ◽  
Lubov Nizhegorodtseva ◽  
Daria Stepankova ◽  
Gulnaz Shaimullina ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Seed Treatment ◽  
Spring Barley ◽  
Trichoderma Viride ◽  
Biological Agents ◽  
Field Conditions ◽  
Streptomyces Sp ◽  
Rhizospheric Bacteria ◽  
Barley Resistance

The aim of the article is to study the effect of various biological agents of biofungicides on plant resistance to drought and formation of spring barley crops. Endophytic bacteria (Bacillus subtilis), rhizospheric bacteria (Pseudomonas fluorescens), actinomycetes (Streptomyces sp.), and micromycetes (Trichoderma viride) were used as bioagents of biofungicides. Preparations based on biological agents were used to treat spring barley seeds. The studies were carried out in laboratory and field conditions. In the conditions of the model artificial acute drought, it was found that seed treatment with Streptomyces sp. Stimulates the leaf and root growth, as well as increases peroxidase activity in the leaves. The maximum content of proline was during seed treatment with Pseudomonas fluorescens. An increase in the content of chlorophyll was observed when treating with Trichoderma viride seeds. In the field conditions, Pseudomonas putida and Streptomyces were more efficient by the content of proline in seedlings. In terms of the spring barley yield, seed treatment with Streptomyces sp., Pseudomonas putida and Bacillus subtilis was more efficient. Streptomyces sp., Pseudomonas putida and Bacillus subtilis are promising for increasing barley resistance to drought.

Properties of the reversible nonoxidative vanillate / 4-hydroxybenzoate decarboxylase from Bacillus subtilis

2008 ◽  
Vol 54 (1) ◽  
pp. 75-81 ◽  
Author(s):  
Boguslaw Lupa ◽  
Delina Lyon ◽  
Lindsey N. Shaw ◽  
Magdalena Sieprawska-Lupa ◽  
Juergen Wiegel
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Gene Sequence ◽  
Specific Activity ◽  
Kinetic Properties ◽  
Carboxylase Activity ◽  
Native Form ◽  
Streptomyces Sp ◽  
Sequence Identification ◽  
Bacillus Subtilis Atcc

Bacillus subtilis (ATCC 6051) reversibly decarboxylates vanillate and 4-hydroxybenzoate under both aerobic and anoxic conditions. Thus, we have identified on the basis of gene sequence homology with Sedimentibacter hydroxybenzoicus and Streptomyces sp. strain D7, a putative B. subtilis hydroxybenzoate decarboxylase. The native form of this enzyme is encoded by 3 genes yclBCD (GI Sequence Identification Nos.: 2632649, 2632650, 2632651) that we have renamed during this research as bsdBCD to align with existing nomenclature. The bsdD gene is reported in the database to be 690 bp; however, our sequence analysis revealed that the size of this gene is in fact 228 bp, an observation that results in a shortening of YclD (i.e., BsdD) from 229 to 75 aa. The corresponding bsdBCD genes were cloned into Escherichia coli , and the heterologously expressed enzyme was assayed for activity. The decarboxylase exhibited a narrow substrate range, with only 2 of the tested substrates, vanillate (Kmapp = 4 mmol·L–1) and 4-hydroxybenzoate (Kmapp = ~1 mmol·L–1), being decarboxylated. The recombinant enzyme had properties similar to that of the native enzyme in respect to specific activity, kinetic properties, bidirectional decarboxylase–carboxylase activity, oxygen insensitivity, and substrate specificity.

scholarly journals Biocontrol del marchitamiento vascular del frijol, causado por Fusarium oxysporum empleando Rizobacterias Promotoras del Crecimiento Vegetal (PGPR).

2019 ◽  
Vol 6 (1) ◽  
pp. 9-16
Author(s):  
Javier Soto Valenzuela ◽  
María Reyes Córdova ◽  
CA Cadenas-Giraldo
Keyword(s):  
Bacillus Subtilis ◽  
Phaseolus Vulgaris ◽  
Fusarium Oxysporum ◽  
Bacillus Sp ◽  
Streptomyces Sp

La marchitez vascular causada por Fusarium oxysporum en Phaseolus vulgaris (frijol común) es un problema fitosanitario que afecta directamente al rendimiento y economía de los agricultores, para su control se usan productos químicos de contacto; sin embargo, una alternativa a este uso es el biocontrol, empleando organismos promotores de crecimiento vegetal (PGPR) con buena capacidad antagónica. En este trabajo se comparó géneros bacterianos con características PGPR; Bacillus (Bacillus sp. “a”, Bacillus sp. “b”, Rhizobium (CIAT 899), Actinobacteria (Streptomyces sp.), Prochloraz como control químico y los formulados con Azotobacter sp., y Bacillus subtilis como controles positivos. Se presentaron como mejores candidatos a PGPR y biocontroladores las cepas de Bacillus“a” y Actinobacteria, con una severidad de 1 y 3 grados, incidencia antagónica de 61.54 y 76.93%, peso seco de 0.42 y 0.31g y una longitud total de 17.23 y18 cm, respectivamente. El objetivo de este trabajo fue evaluar el biocontrol frente a F. oxysporum generado por bacterias tipo PGPR.

2-Alkyl-3,4-dihydroxy-5-hydroxymethylpyridine Derivatives: New Natural Vitamin B6 Analogues from a Terrestrial Streptomyces sp.

2005 ◽  
Vol 60 (1) ◽  
pp. 63-66 ◽  
Author(s):  
Rajendra P. Maskey ◽  
Felix Huth ◽  
Iris Grün-Wollny ◽  
Hartmut Laatsch
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
Natural Product ◽  
Anthranilic Acid ◽  
Vitamin B6 ◽  
Ethyl Acetate Extract ◽  
Mucor Miehei ◽  
Streptomyces Sp

The ethyl acetate extract of the strain Streptomyces sp. GW23/1540 has yielded four new 2-alkyl-5-(hydroxymethyl)pyridine-3,4-diols, 5-hydroxymethyl-2-isopropyl-pyridine-3,4-diol (1a), 5-hydroxymethyl-2-propyl-pyridine-3,4-diol (1b), 2-sec-butyl-5-hydroxymethyl-pyridine-3,4-diol (1c), and 5-hydroxymethyl-2-isobutyl-pyridine-3,4-diol (1d). Similarly, the strain Streptomyces sp. GW63/1571 afforded 2-sec-butyl-5-hydroxymethyl-pyridine-3,4-diol (1c) and another new natural product, (3aS, 7aR)-3a-hydroxy-3a,4,7,7a-tetrahydro-1-benzofuran-2(3H)-on e (3), together with anthranilic acid, anthranilamide, and phenylacetamide. The new natural products were inactive against three micro algae, the fungus Mucor miehei, the yeast Candida albicans, and the bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Streptomyces viridochromogenes.

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