Potential Bacterial Antagonists from Cowshed Air for the Management of Fusarium Pathogens in Stored Rice

Rice is the principal staple food for more than half population of earth which is infested by many pathogens including Fusarium . Numbers of Fusarium species are responsible for causing pathogenic implications in rice like bakanae, rot, blight, etc. Majority of them produce mycotoxins which are responsible for human and animal toxicity and the cause of cancer disease. Adoption of biological control methods utilizing microbial antagonists might be an eco-friendly option. Bacterial species including Bacillus species have been isolated from various sources for utilisation as biocontrol agents to combat crop pathogens. Cow dung and the cow shed air have been a good source of such antagonistic bacteria. Hence, in the current study eighteen bacteria (BC1 to BC18) including Bacillus species have been isolated from cow shed air and paddy seeds stored in cowshed of Odisha, India. Bacteria isolated from domestic cowshed showed excellent inhibitory capacity than those of commercial cowshed against pathogenic Fusarium F90 and pathogenic as well as fumonisin producing Fusarium F55. Non-fumonisin producer Fusarium F90 was inhibited relatively with higher degree by all the antagonistic bacteria even it was completely suppressed by BC6 after three days of interaction. Paddy seeds stored in cowshed were found to be saturated with cowshed antagonistic bacteria. These bacterial antagonists hold potential to be utilized as Biological Control Agents (BCA) for safeguarding rice production. Investigation on more number of bacterial species from more cowsheds will definitely give more insights in the pattern and mode of inhibition.

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1708 - Compatible mixtures of antagonistic bacteria developed for biological control of Pectobacterium spp. and Dickeya spp. in potato

10.26226/morressier.5b5199c4b1b87b000ecee965 ◽

2018 ◽

Author(s):

Robert Czajkowski ◽

Dorota Krzyżanowska ◽

Sylwia Jafra

Keyword(s):

Biological Control ◽

Antagonistic Bacteria

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Field Evaluation of Biological Control of Fire Blight in the Eastern United States

Plant Disease ◽

10.1094/pdis-93-4-0386 ◽

2009 ◽

Vol 93 (4) ◽

pp. 386-394 ◽

Cited By ~ 47

Author(s):

George W. Sundin ◽

Nicole A. Werner ◽

Keith S. Yoder ◽

Herb S. Aldwinckle

Keyword(s):

United States ◽

New York ◽

Biological Control ◽

Fire Blight ◽

Field Evaluation ◽

Pantoea Agglomerans ◽

Eastern United States ◽

Bacterial Antagonists ◽

Bacterial Endospores ◽

Control Options

The bacterial antagonists Pseudomonas fluorescens A506, Pantoea agglomerans C9-1, and Pantoea agglomerans E325 and preparations of Bacillus subtilis QST 713 containing bacterial endospores and lipopeptide metabolites were evaluated for efficacy in controlling fire blight in Michigan, New York, and Virginia. When examined individually, the biological control materials were not consistently effective in reducing blossom infection. The average reduction in blossom infection observed in experiments conducted between 2001 and 2007 was variable and ranged from 9.1 to 36.1%, while control with streptomycin was consistent and ranged from 59.0 to 67.3%. Incidence of blossom colonization by the bacterial antagonists was inconsistent, and <60% of stigmata had the antagonists present in 12 of 25 experiments. Consistent control of blossom infection was observed when the biological control materials were integrated into programs with streptomycin, resulting in a reduction of the number of streptomycin applications needed to yield similar levels of control. Our results indicate that the prospects for biological control of fire blight in the eastern United States are currently not high due to the variability in efficacy of existing biological control options.

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Discovery and Characterization of Low-Molecular Weight Inhibitors of Erwinia tracheiphila

Phytopathology ◽

10.1094/phyto-11-19-0440-r ◽

2020 ◽

Vol 110 (5) ◽

pp. 989-998

Author(s):

Cláudio M. Vrisman ◽

Loïc Deblais ◽

Yosra A. Helmy ◽

Reed Johnson ◽

Gireesh Rajashekara ◽

...

Keyword(s):

Pseudomonas Syringae ◽

High Throughput Screening ◽

Pathogenic Bacteria ◽

Bacterial Species ◽

Bacillus Species ◽

Erwinia Tracheiphila ◽

Static Activity ◽

Low Toxicity

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.

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Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

The Scientific World JOURNAL ◽

10.1100/2012/723293 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

M. M. Rahman ◽

M. E. Ali ◽

A. A. Khan ◽

A. M. Akanda ◽

Md. Kamal Uddin ◽

...

Keyword(s):

Biological Control ◽

Biological Control Agent ◽

Erwinia Carotovora ◽

Soft Rot ◽

Control Agent ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

Antagonistic Bacteria ◽

And Storage

A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacteriumErwinia carotovorasubsp.carotovora(Ecc) were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was testedin vitroagainst the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited thein vitrogrowth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genusBacillusand the isolate E-45 asLactobacillussp. The stronger antagonistic activity against Ecc P-138 was found in E-65in vitroscreening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5%) antagonistic effect of E-65 was observed in the Granola and the lowest (32.7%) of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

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Seleksi Bakteri Antagonis untuk Mengendalikan Layu Fusarium pada Tanaman Phalaenopsis

Jurnal Hortikultura ◽

10.21082/jhort.v22n3.2012.p276-284 ◽

2013 ◽

Vol 22 (3) ◽

pp. 276 ◽

Cited By ~ 1

Author(s):

Ika Djatnika

Keyword(s):

Fusarium Oxysporum ◽

Fusarium Wilt ◽

Wilt Disease ◽

Antagonistic Bacteria ◽

Plant Research Institute ◽

Fusarium Spp ◽

Human Environment ◽

Bacterial Antagonists ◽

Important Disease ◽

Selection Of

ABSTRAK. Layu Fusarium merupakan penyakit penting yang menjadi kendala dalam memproduksi tanaman anggrek. Untuk mengendalikannya, petani masih menggunakan fungsida. Tanaman anggrek kerap ditampilkan sebagai hiasan yang dekat dengan lingkungan manusia, maka penggunaan pestisida perlu diperhatikan. Oleh karena itu sangat penting dicari cara pengendalian lainnya yang aman terhadap lingkungan, antara lain dengan pengendalian hayati. Tujuan penelitian ialah mendapatkan isolat bakteri antagonis yang dapat mengendalikan layu Fusarium pada tanaman Phalaenopsis. Percobaan dilakukan di Laboratorium dan Rumah Kasa Balai Penelitian Tanaman Hias Segunung (1100 m dpl.) serta untuk mikrob diisolasi dari lokasi tanaman hortikultura di Jawa Barat dan DKI Jakarta, mulai Bulan Januari sampai dengan Desember 2010. Penelitian meliputi isolasi Fusarium spp. sebagai patogen pada tanaman anggrek di beberapa lokasi, isolasi bakteri antagonis, uji kemangkusan bakteri terhadap pertumbuhan Fusarium spp. di laboratorium, dan uji kemangkusan bakteri antagonis terhadap layu Fusarium di rumah kasa. Hasil penelitian menunjukkan bahwa penyebab layu Fusarium pada tanaman Phalaenopsis ialah Fusarium oxysporum. Dari 154 isolat bakteri yang diisolasi dari lapangan, hanya ada tiga isolat yaitu nomor B23, B 26, dan B37 yang dapat menekan pertumbuhan F. oxysporum pada media PDA. Sampai dengan pengamatan minggu ke-10 setelah inokulasi, ketiga bakteri tersebut masing-masing menekan jumlah tanaman yang terserang layu Fusarium, yaitu sebesar 46,9; 48,9; dan 65,3%, dan masing-masing menekan intensitas penyakit layu 50,5; 43,9; dan 55,1%.ABSTRACT. Djatnika, I 2012. Selection of Antagonistic Bacteria for Controlling of Fusarium Wilt on Phalaenopsis Plants. Fusarium wilt is an important disease as constraint on production of orchid plants. The control of Fusarium wilt of orchids with fungicides often use by farmers. Orchid plants are often displayed as a decoration which is close to the human environment, so the application of pesticides have to get attention. It is therefore necessary to find another method that is safe for environments, such as using of biological control. The purpose of the study was to get isolates of bacterial antagonists for controlling of Fusarium wilt of Phalaenopsis plants. The experiment was conducted at Laboratory and Screenhouse of Indonesian Ornamental Plant Research Institute, Segunung (1100 m asl.) and the microbes were isolated from horticultural area in West Java and DKI Jakarta since January until December 2010. The research comprised of isolation of Fusarium spp. from orchid plants in some location, isolation of bacterial antagonists, the effectiveness of the bacteria to suppress Fusarium spp. growth in laboratory, and the effectiveness of the bacteria to control Fusarium wilt on Phalaenopsis plants in the screenhouse. The results showed that the causal Fusarium wilt of Phalaenopsis plants was identified as Fusarium oxysporum. Three of 154 isolates of bacteria, i.e. isolates number of B23, B26, and B37, could suppress of F. oxysporum growth on PDA media. Observation up to 10 weeks after inoculation, the three bacteria could reduce the number of plants attacked by Fusarium wilt , which were 46.9; 48.9; and 65.3% respectively, and each of them suppress wilt disease intensity 50.5, 43.9, and 55.1% respectively.

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Hidden reservoirs of pathogens in dental settings

Bioinformation ◽

10.6026/97320630017073 ◽

2021 ◽

Vol 17 (1) ◽

pp. 73-79

Author(s):

Silpi Chatterjee ◽

Keyword(s):

Staphylococcus Aureus ◽

Mobile Phones ◽

Nosocomial Infections ◽

Bacterial Species ◽

Brain Heart Infusion ◽

Bacillus Species ◽

Coagulase Negative Staphylococcus ◽

Cross Contamination ◽

Sterile Saline ◽

Predominant Species

Nosocomial infections are a major concern to both clinicians and health care seekers. Investigations have suggested that laptops & mobile phones may contribute to cross-contamination and can serve as vehicles for infection transmission. Therefore, it is of interest to document the data on hidden reservoirs such as mobile phones and laptops of pathogens in dental settings at the Hazaribag college of dental sciences and Hospital, Jharkhand. The samples were collected from 25 laptops and 25 mobile phones from dentists working in a dental college in Hazaribag city. The samples were collected aseptically using sterile cotton swabs dipped in sterile saline by rotating the swabs on the keyboard surfaces of laptops and mobile phones, inoculated into Brain Heart Infusion broth, vortexed for 1 minute in Fischer Vortex Genie 2 on highest setting & streaked immediately on 5% sheep blood agar plates and were incubated at 370C for 24 hours aerobically. The isolates were identified based on the colony morphology, colony characteristics and biochemical reactions. The bacterial species isolated were Staphylococcus aureus, Coagulase negative Staphylococcus, Bacillus species, Enterococci, Micrococci, and Pseudomonas etc. Predominant species isolated was Staphylococcus aureus and least was Micrococci. Higher percentage of organisms was found at the Department of Periodontics, Endodontics and least was found in Department of Public Health Dentistry. The percentage and type of organism isolated from keyboards of laptops and mobile phones were similar. Thus, laptops and mobile phones act as vehicles for transfer of potential pathogens associated with dental hospitals. Disinfecting the hands prior to examination of patients and disinfection of laptops and mobiles with alcohol wipes should be done to prevent nosocomial infections.

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