Psychrotolerant polychlorinated biphenyl (PCB)-degrading bacteria were isolated at 7 degreesC from PCB-contaminated Arctic soil by using biphenyl as the sole organic carbon source. These isolates were distinguished from each other by differences in substrates that supported growth and substrates that were oxidized. 16S ribosomal DNA sequences suggest that these isolates are most closely related...

Soil bacteria belonging to the genus Azotobacter, Pantoea and some unidentified soil isolates were tested in vitro for phytohormone production under laboratory and soil conditions. The German wheat variety Munk was inoculated by several soil bacteria with exogenously applied hormones (IAA, 2,4-D) and a flavonoid (naringenin) with a half of the amount of recommended doses of fertilizers under gr...

The first rainfall following a severe dry period provides an abrupt water potential change that is both an acute physiological stress and a defined stimulus for the reawakening of soil microbial communities. We followed the responses of indigenous communities of ammonia-oxidizing bacteria, ammonia-oxidizing archaea, and nitrite-oxidizing bacteria to the addition of water to laboratory incubatio...

Microbial communities in soil provide a wide range of ecosystem services. On the small scale, nutrient rich hotspots in soil developed from the activities of animals or plants are important drivers for the composition of microbial communities and their functional patterns. However, in subsoil, the spatial heterogeneity of microbes with differing lifestyles has been rarely considered so far. In ...

Several anthropogenic interventions, common in agriculture, may influence active bacterial communities in soil without affecting their total composition. Therefore, the composition of an active bacterial community in soil may reflect its relation to biogeochemical processes. This issue was addressed during two consecutive years in olive-orchard soil, irrigated with treated wastewater (TWW) in a...

Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community struct...

Rapid responses of bacteria to sudden changes in their environment can have important implications for the structure and function of microbial communities. In this study, we used heavy-water stable isotope probing (H2(18)O-SIP) to identify bacteria that respond to soil rewetting. First, we conducted experiments to address uncertainties regarding the H2(18)O-SIP method. Using liquid chromatograp...

Microbially mediated insoluble technetium (Tc) formation was studied using surface water covering paddy fields. Surface water samples were collected from three kinds of flooded paddy soils: andosol, gley soil, and gray lowland soil. Insoluble Tc (> 0.2 μm in size) was formed in all surface water samples and the amounts ranged from 48.7 ± 2.2% of total Tc (gley soil) to 88.5 ± 3.1% (gray lowland...

In order to evaluate the influence of ionic liquid 1butyl-3-methylimidazolium chloride ([Bmim]Cl) on the soil micro-ecological system, the toxicity of [Bmim]Cl to soil microorganisms and its impact on soil physico-chemical properties were investigated. Three soil samples, which were taken from the rape land, nursery land and the broad bean land respectively, were used for this study. The toxici...

potassium is an essential plant macronutrient. various microorganisms including bacteria and fungi, algae, yeast and mosses are able to decompose silicate minerals and to dissolve nutrient such as k, fe, zn and si. aamong them bacteria are more important. the aim of this study was to determine the ability of microbial populations for releasing soil potassium. this study was carried out as a fac...