Soil Bacteria and Bacteriophages

Abstrak - Produksi padi di Indonesia setiap tahun mengalami peningkatan, namun peningkatan ini belum mampu memenuhi kebutuhan nasional sehingga impor masih harus dilakukan. Salah satu masalah dalam produksi beras adalah penggunaan pupuk berlebih yang tidak hanya meningkatkan biaya produksi, namun juga merusak kondisi tanah. Aplikasi bakteri tanah sebagai Plant Growth Promoting Rhizobacteria (PGPR) dapat menjadi salah satu solusi terhadap masalah ini. Penelitian ini bertujuan untuk mengisolasi bakteri tanah dari 3 lokasi sawah daerah Bekasi, membandingkan keberadaan total bakteri pada ketiga lokasi tersebut, dan melakukan karakterisasi isolat berdasarkan karakter yang dapat memicu pertumbuhan tanaman. Dari ketiga lokasi, diperoleh total 59 isolat dan 5 diantaranya berpotensi sebagai PGPR karena kemampuan fiksasi Nitrogen, melarutkan Fosfat, katalase positif, dan motil. Dari ketiga lokasi pengambilan sampel, BK1 memiliki jumlah total bakteri terendah karena aplikasi pemupukan dan pestisida berlebih yang ditandai tingginya kadar P total, serta tingginya residu klorpirifos, karbofuran, dan paration. Kondisi fisik tanah BK1 juga didominasi partikel liat yang menyebabkan tanah menjadi lebih padat. Peningkatan jumlah penggunaan pupuk tidak selalu diikuti peningkatan produktivitas tanaman. Kata Kunci - Bakteri tanah, Rhizosfer sawah, PGPR, Pupuk Hayati Abstract - Rice production in Indonesia has increased annually, but this increase has not reached national demand,so imports still done. One of the problems in rice production is the use of excessive fertilizers that not only increase production costs, but also decreased the soil conditions. The application of soil bacteria as Plant Growth Promoting Rhizobacteria (PGPR) can be the one solution to face this problem. The objective of this study was isolate soil bacteria from 3 locations of rice field in Bekasi, compare the total bacteria in the three locations, and characterize isolates based on the character that can promote plant growth. From three locations, a total of 59 isolates were obtained and 5 of them were potential as a PGPRs due to its Nitrogen fixation activity, Phosphate solubilization, positive catalase, and motility. From three sampling sites, BK1 has the lowest TPC value because of excessive fertilizers and pesticides application which indicated by high total P levels, and also high chlorpyrifos, carbofuran and paration residues. The physical condition of BK1 soil is also dominated by clay particles which causes the soil more solid. Increasing of fertilizer application is not always followed by increased plant productivity. Keywords - Biofertilizer, PGPR, Rice field rhizosphere, Soil Bacteria

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Biodegradation of organophosphorus Pollutants by Soil Bacteria: Biochemical Aspects and Unsolved Problems

Biotekhnologiya ◽

10.21519/0234-2758-2020-36-4-126-135 ◽

2020 ◽

Vol 36 (4) ◽

pp. 126-135

Author(s):

T.V. Shushkova ◽

D.O. Epiktetov ◽

S.V. Tarlachkov ◽

I.T. Ermakova ◽

A.A. Leontievskii

Keyword(s):

Genome Sequencing ◽

Soil Bacteria ◽

Activity Regulation ◽

Bacterial Isolates ◽

Bacterial Strains ◽

Russian Science ◽

Degrading Bacteria ◽

Phosphorus Source ◽

Glyphosate Herbicide ◽

Enzymatic Pathways

The degradation of persistent organophosphorus pollutants have been studied in 6 soil bacterial isolates and in 3 bacterial strains adapted for utilization of glyphosate herbicide (GP) under laboratory conditions. Significant differences in the uptake of organophosphonates were found in taxonomically close strains possessing similar enzymatic pathways of catabolism of these compounds, which indicates the existence of unknown mechanisms of activity regulation of these enzymes. The effect of adaptation for GP utilization as a sole phosphorus source on assimilation rates of several other phosphonates was observed in studied bacteria. The newly found efficient stains provided up to 56% of GP decomposition after application to the soil in the laboratory. The unresolved problems of microbial GP metabolism and the trends for further research on the creation of reliable biologicals capable of decomposing organophosphonates in the environment are discussed. organophosphonates, glyphosate, biodegradation, bioremediation, C-P lyase, phosphonatase, degrading bacteria Investigation of phosphonatase and genome sequencing were supported by Russian Science Foundation Grant no. 18-074-00021.

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Distribution of Enteric Viruses and Microorganisms in Long-Term Sewage-Treated Soil

Water Science & Technology ◽

10.2166/wst.1983.0046 ◽

1983 ◽

Vol 15 (5) ◽

pp. 129-135 ◽

Cited By ~ 2

Author(s):

Z Filip ◽

K Seidel ◽

H Dizer

Keyword(s):

Soil Bacteria ◽

Pathogenic Bacteria ◽

Sewage Treatment ◽

Anaerobic Bacteria ◽

Enteric Viruses ◽

Sewage Irrigation ◽

Groundwater Samples ◽

West Berlin ◽

Aerobic Soil

To determine whether long-term sewage treatment can take place without a pollution risk for soil and groundwater, samples from sewage irrigation fields in West Berlin which have been in use since about 1890 were analyzed for enteric viruses and microorganisms. Enteric viruses were detected in only seven samples from a total number of eighty seven taken from different soil depths. With only one exception, no viruses were found below 60 cm. No viruses were detected in groundwater samples. Long-term sewage irrigation did not result in significant changes in the colony courts of aerobic soil bacteria, but the counts of anaerobic bacteria and actinomycetes were slightly elevated and those of microscopic fungi slightly decreased. Potentially pathogenic bacteria were not detected in soil below 90 cm.

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Soil Bacteria Use Racemases To Detoxify, Grow on D-Amino Acids

Microbe Magazine ◽

10.1128/microbe.9.309.1 ◽

2014 ◽

Vol 9 (8) ◽

pp. 309-309

Author(s):

Barry E. DiGregorio

Keyword(s):

Amino Acids ◽

Soil Bacteria

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