scholarly journals  Management of bacterial blight of cotton using a mixture of Pseudomonas fluorescens and Bacillus subtilis

2010 ◽  
Vol 46 (No. 2) ◽  
pp. 41-50 ◽  
Author(s):  
K. Salaheddin ◽  
V. Valluvaparidasan ◽  
D. Ladhalakshmi ◽  
R. Velazhahan
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Bacterial Blight ◽  
Maximum Yield ◽  
Biochemical Properties ◽  
Field Conditions ◽  
Phenotypic Characteristics ◽  
Polymerase Chain ◽  
Number Of Branches

The potential of antagonistic rhizobacteria in the management of bacterial blight of cotton caused by Xanthomonas axonopodis pv. malvacearum (Xam) was evaluated under greenhouse and field conditions. In this study, 93 bacterial isolates from the rhizosphere of cotton were screened for their efficacy in inhibiting the growth of Xam in vitro. Among them, 21 isolates were found to inhibit the in vitro growth of Xam. These isolates were identified as Pseudomonas fluorescens and Bacillus subtilis based on phenotypic characteristics, biochemical properties and using 16S-23S intergenic transcribed spacer-Polymerase Chain Reaction (PCR). Among the 21 isolates, the isolates P. fluorescens Pf32 and P. fluorescens Pf93 and B. subtilis B49 exhibited the maximum inhibitory activity against Xam. Talc-based powder formulations of the effective antagonistic isolates of P. fluorescens (Pf32, Pf93) and B. subtilis (B49) were developed and evaluated individually and in combination for their efficacy in the management of bacterial blight of cotton under greenhouse and field conditions. The P. fluorescens isolates Pf32 and Pf93 and Bacillus subtilis isolate B49 survived well in the talc-based formulation for more than 90 days. The application of a mixture of Pf32, Pf93 and B49 to seed, soil and foliage significantly reduced the bacterial blight incidence and increased the plant height, number of branches and number of bolls under field conditions. The plots treated with a mixture of Pf32, Pf93 and B49 recorded the maximum yield of 1915 kg/ha and 1512 kg/ha in trial I and trial II compared to 1210 kg/ha and 987 kg/ha in the untreated control, respectively.

scholarly journals Rizobacterias con potencial antagonista in vitro a Mycosphaerella fijiensis Morelet

2020 ◽  
Vol 13 (2) ◽  
Author(s):  
Karen Tatiana Chávez Arteaga ◽  
Jefferson Javier Guato Molina ◽  
Jorge Luis Rodríguez Acosta ◽  
Ángel Virgilio Cedeño Moreira ◽  
Ricardo Fernando Romero Meza ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Putida ◽  
Serratia Marcescens ◽  
Pseudomonas Fluorescens ◽  
Mycosphaerella Fijiensis ◽  
Subtilis Atcc ◽  
Bacillus Subtilis Atcc ◽  
Pseudomonas Veronii ◽  
Enterobacter Asburiae

El empleo de bio-controladores en la agricultura beneficia los aspectos fisiológicos en plantas, a diferencia de la constante aplicación de pesticidas en el cultivo del banano ha ocasionado la pérdida de la sensibilidad en M. fijiensis, reduciendo la microbiota del suelo. El objetivo se enfocó en caracterizar el potencial antagónico de las PGPR en inhibición de germinación de ascósporas y desarrollo micelial de M. fijiensis. Se realizaron cultivos monospóricos de M. fijiensis e identificado por PCR. Se evaluaron los extractos celulares de Pseudomonas putida PB3-6, Klebsiella variicola BO3-4, Enterobacter asburiae BA4-19, Serratia marcescens PM3-8, Enterobacter asburiae PM3-14, Pseudomonas protegens CHA0, Pseudomonas fluorescens WCS417, Pseudomonas veronii R4 y Bacillus subtilis ATCC 5540 para sus evaluaciones antagonistas: a) Inhibición del tubo germinativo de las ascósporas al 2% y b) Desarrollo micelial al (2 y 10 %). La PCR empleado en la identificación de M. fijiensis se confirma el producto de amplificación de 1018 pb. El factor antagónico de los extractos celulares al 2 % de PM3-14 y CHA0 inhibe sobre el 80 % al desarrollo de los tubos germinativos. La inhibición al desarrollo micelial del extracto celular al 2 %, de CHA0 logró una efectividad del 54 % y las cepas (PM3-8, PM3-14 y BA4-19) con (32, 26 y 26 %). Al 10 % del extracto de la cepa PM3-8 inhibe el desarrollo micelial con niveles de turbidez de 0,47 (OD600nm). El empleo de estos bio-controladores en la agricultura ofrecerá una alternativa para beneficiar en la reducción del uso de agroquímicos

In vitro evaluation of bio-agents against Pyricularia oryzae (Cav.) causing rice blast disease

2017 ◽  
Vol 37 (03) ◽  
Author(s):  
Akhilesh Kumar Kulmitra ◽  
Neha Sahu ◽  
V.B. Sanath Kumar ◽  
Thejesha A. G. ◽  
Amlan Ghosh ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Rice Blast ◽  
Mycelial Growth ◽  
Trichoderma Viride ◽  
Culture Technique ◽  
Pyricularia Oryzae ◽  
Blast Disease ◽  
Dual Culture

The five different bio-agents viz., Trichoderma viride, T. harzianum, T. virens, Pseudomonas fluorescens and Bacillus subtilis were evaluated against Pyricularia oryzae at four and eight days after incubation through dual culture technique. Among the five different bio-agents, highest per cent inhibition of mycelial growth of fungus was recorded in T. virens i.e. 67 per cent and 70 percent after four and eight days after incubation respectively with mean of 68.5 per cent followed by Trichoderma viride with the inhibition of 61 and 63 per cent respectively with mean of 62 per cent. The Pseudomonas fluorescens did not show any inhibition of mycelial growth of P. oryzae as the pathogen over grew the bio-agents.

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.

scholarly journals Penapisan Beberapa Isolat Pseudomonas fluorescens, Bacillus subtilis dan Trichoderma harzianum yang bersifat Antagonistik terhadap Ralstonia solanacearum pada Tanaman Kentang

Agrikultura ◽  
2009 ◽  
Vol 20 (3) ◽  
Author(s):  
Hersanti Hersanti ◽  
Rian Triyanti Rupendi ◽  
Andang Purnama ◽  
Hanudin Hanudin ◽  
Budi Marwoto ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Trichoderma Harzianum ◽  
Ralstonia Solanacearum

Penyakit layu bakteri yang disebabkan oleh R. solanacearum merupakan salah satu penyakit penting yang menyerang tanaman kentang. Salah satu alternatif pengendalian yang ramah lingkungan adalah menggunakan mikroba antagonis seperti Pseudomonas fluorescens, Bacillus subtilis, dan Trichoderma harzianum. Tujuan penelitian adalah  untuk mendapatkan isolat mikroba antagonis terbaik yang paling menekan  penyakit layu bakteri pada tanaman kentang.  Dua percobaan pada penelitian ini menggunakan  Rancangan Acak Lengkap. Percobaan  in vitro menguji daya hambat tiga isolat  P. Fluorescens,  dua isolat B. subtilis, satu isolat B. cereus dan  3 isolat T. harzianum terhadap perkembangan koloni  R. solanacearum pada media King’s B. Percobaan  in vivo menguji kemampuan seluruh isolat terhadap penekanan serangan penyakit layu pada tanaman kentang.  Hasil percobaan menunjukkan bahwa isolat T. harzianum 1, T. harzianum 2 dan T. harzianum 3 mampu menekan penyakit layu bakteri pada tanaman kentang dengan persentase penghambatan berturut-turut 77,21 %,  77,21 %, dan 63,57 %.

scholarly journals Avaliação da compatibilidade in vitro de microrganismos (Bacillus subtilis, Pseudomonas fluorescens e Trichoderma atroviride) com fungicidas comerciais, para a produção sustentável de amendoim

2021 ◽  
Vol 2 (edesp2) ◽  
pp. e21112
Author(s):  
Dean Fernandez ◽  
Matias Torassa ◽  
Maria Alejandra Pérez
Keyword(s):  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Trichoderma Atroviride

A aplicação de fungicidas na semente de amendoim é uma necessidade na semeadura, porém a aplicação combinada com produtos biológicos pode reduzir os efeitos do uso de agroquímicos, favorecendo a qualidade do grão como alimento. O objetivo deste trabalho foi avaliar a compatibilidade in vitro de microrganismos (Bacillus subtilis, Pseudomonas fluorescens e Trichoderma atroviride) com fungicidas comerciais para a produção sustentável de amendoim. Os testes de compatibilidade foram realizados no Laboratório do Centro de Transferência de Qualidade Agroalimentar (FCA UNC). Foram avaliados três combinações de fungicidas comerciais disponíveis no setor de amendoim (F1, F2, F3), em diferentes doses (0, 30, 50, 100 e 1000 mg.l-1). Em placas de petri com meio APG com cada fungicida, foram inseridos B. subtilis, P. fluorescens e T. atroviride, que foram mantidos em câmaras com condições controladas. Sete dias após a semeadura, o crescimento bacteriano foi avaliado de acordo com a escala de compatibilidade e para Trichoderma foi calculada a porcentagem de inibição do crescimento radial (PICR). O delineamento foi completamente aleatório; para cada biológico, foram avaliadas três repetições para cada fungicida e dose. Todo o teste foi repetido três vezes. Os dados foram submetidos à análise de variância e os valores médios do PICR foram comparados por Tukey (p<0,05). Os resultados mostraram um efeito diferencial dos fungicidas sobre os biológicos. F1 (Tiabendazol + Fludioxonil + Metalaxil-M + Azoxistrobina) pode ser combinado com P. fluorescens em todas as doses e B. subtilis em doses não superiores a 50 mg.l-1. F2 (Ipconazol + Metalaxil) e F3 (Ipconazol + Metalaxil M + Carboxina) podem ser aplicados com P. fluorescens mesmo em altas concentrações. Apenas F3 pode ser combinado com T. atroviride até 100 mg.l-1. A combinação correta de fungicidas e produtos biológicos contribuirá efetivamente para a sustentabilidade do sistema de produção de amendoim.

Different Responses of Planktonic and Attached Bacillus subtilis and Pseudomonas fluorescens to Sanitizer Treatment

1999 ◽  
Vol 62 (4) ◽  
pp. 368-379 ◽  
Author(s):  
D. LINDSAY ◽  
A. von HOLY
Keyword(s):  
Electron Microscopy ◽  
Hydrogen Peroxide ◽  
Scanning Electron Microscopy ◽  
Bacillus Subtilis ◽  
Pseudomonas Fluorescens ◽  
Chlorhexidine Gluconate ◽  
Plate Counts ◽  
Sessile Cells ◽  
Scanning Electron

Three commercial sanitizers containing iodophor (I), peracetic acid/hydrogen peroxide (PAH), or chlorhexidine gluconate (CG) were evaluated in vitro against planktonic and sessile Bacillus subtilis or Pseudomonas fluorescens cells grown in Standard One Nutrient Broth. Sessile cells were attached to stainless steel or polyurethane test surfaces. Planktonic and attached cells of both bacteria were enumerated by plate counts after sanitizer treatment for 1, 3, or 5 min. Sessile cells were dislodged from test surfaces by shaking them with beads. Cell morphologies were monitored by scanning electron microscopy (SEM). Attached B. subtilis and P. fluorescens cells on both surface types were less susceptible to all three sanitizers than their planktonic counterparts. PAH, I, and CG were equally effective against planktonic P. fluorescens cells, which were reduced by 99.999% after 1, 3, and 5 min exposure. PAH was the only sanitizer effective against attached P. fluorescens cells on both surface types; it reduced counts by ≤99.9% after 1, 3, and 5 min exposure. PAH was also the most effective sanitizer against planktonic B. subtilis cells, reducing counts by 99.9% after 1, 3, and 5 min. Sessile B. subtilis cells on both surface types were the least susceptible to all sanitizers; counts were reduced by only 99.5% or less after exposure to PAH for 5 min. SEM revealed that planktonic and attached cells of both bacteria exhibited symptoms of surface roughness, indentations, and shape distortions after treatment with any of the sanitizers.

scholarly journals Combination of Different Antagonistic Bacteria to Control of Potato Blackleg Disease Caused by Pectobacterium atrosepticum under Greenhouse and Field Conditions

2016 ◽  
Vol 5 (1) ◽  
pp. 35-43 ◽  
Author(s):  
Hoda H. El-Hendawy ◽  
Kamal A. M. Abo-Elyousr
Keyword(s):  
Bacillus Subtilis ◽  
Indole Acetic Acid ◽  
Field Conditions ◽  
Antagonistic Bacteria ◽  
Bacterial Isolates ◽  
Blackleg Disease ◽  
Pectobacterium Atrosepticum ◽  
Potato Plants ◽  
Black Leg

Three different antagonistic bacterial isolates, Pseudomonas fluoresces (Pf2), Bacillus subtilis(Bs3) and Rahnella acquatilis (Ra39) restricted the growth of Pectobacterium atrosepticum, the causal agent of black leg disease of potato, in vitro.   Under greenhouse and field conditions, potato plants pre-treated with the three antagonistic bacterial isolates, individually or in combination, showed reduced disease severity relative to non-treated control plants. All isolates produced siderophores in different degrees but did not produce indole acetic acid (IAA) or hydrogen cyanide (HCN).The obtained results indicated that combination of Pseudomonas fluoresces (Pf2), Bacillus subtilis (Bs3) and Rahnella acquatilis (Ra39) is beneficial in controlling black leg disease of potato caused by pectobacterium atrosepticum.

scholarly journals Endophytic Bacteria Bacillus subtilis, Isolated from Zea mays, as Potential Biocontrol Agent against Botrytis cinerea

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 492
Author(s):  
Hernando José Bolivar-Anillo ◽  
Victoria E. González-Rodríguez ◽  
Jesús M. Cantoral ◽  
Darío García-Sánchez ◽  
Isidro G. Collado ◽  
...  
Keyword(s):  
Zea Mays ◽  
Bacillus Subtilis ◽  
Botrytis Cinerea ◽  
Endophytic Bacteria ◽  
Biochemical Properties ◽  
Plant Diseases ◽  
Phytopathogenic Fungus ◽  
Economic Losses

Plant diseases are one of the main factors responsible for food loss in the world, and 20–40% of such loss is caused by pathogenic infections. Botrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It is responsible for incalculable economic losses due to the large number of host plants affected. Today, B. cinerea is controlled mainly by synthetic fungicides whose frequent application increases risk of resistance, thus making them unsustainable in terms of the environment and human health. In the search for new alternatives for the biocontrol of this pathogen, the use of endophytic microorganisms and their metabolites has gained momentum in recent years. In this work, we isolated endophytic bacteria from Zea mays cultivated in Colombia. Several strains of Bacillus subtilis, isolated and characterized in this work, exhibited growth inhibition against B. cinerea of more than 40% in in vitro cultures. These strains were characterized by studying several of their biochemical properties, such as production of lipopeptides, potassium solubilization, proteolytic and amylolytic capacity, production of siderophores, biofilm assays, and so on. We also analyzed: (i) its capacity to promote maize growth (Zea mays) in vivo, and (ii) its capacity to biocontrol B. cinerea during in vivo infection in plants (Phaseolus vulgaris).

Characterization of the Original Christmas Disease Mutation (Cysteine 206 → Serine): From Clinical Recognition to Molecular Pathogenesis

1992 ◽  
Vol 67 (01) ◽  
pp. 063-065 ◽  
Author(s):  
Sherryl A M Taylor ◽  
Jacalyn Duffin ◽  
Cherie Cameron ◽  
Jerome Teitel ◽  
Bernadette Garvey ◽  
...  
Keyword(s):  
Nucleotide Substitution ◽  
Novel Mutation ◽  
Factor Ix ◽  
Causative Mutation ◽  
Coding Region ◽  
Body Of Knowledge ◽  
Polymerase Chain ◽  
Splice Junctions

SummaryChristmas disease was first reported as a distinct clinical entity in two manuscripts published in 1952 (1, 2). The eponym associated with this disorder, is the surname of the first patient examined in detail and reported by Biggs and colleagues in a paper describing the clinical and laboratory features of seven affected individuals (3). This patient has severe factor IX coagulant deficiency (less than 0.01 units/ml) and no detectable circulating factor IX antigen (less than 0.01 units/ml). Coding sequence and splice junctions of the factor IX gene from this patient have been amplified in vitro through the polymerase chain reaction (PCR). One nucleotide substitution was identified at nucleotide 30,070 where a guanine was replaced by a cytosine. This mutation alters the amino acid encoded at position 206 in the factor IX protein from cysteine to serine. The non conservative nature of this substitution, the absence of this change in more than 200 previously sequenced factor IX genes and the fact that the remainder of the coding region of this gene was normal, all provide strong circumstantial evidence in favour of this change being the causative mutation in this patient. The molecular characterization of this novel mutation in the index case of Christmas disease, contributes to the rapidly expanding body of knowledge pertaining to Christmas disease pathogenesis.

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