• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.179-188
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• 2014

This research reports the effects of shifting cultivation on soil environment collecting samples from 0-5 cm soil depth from five locations viz. at Burburichhara, Maichchari, Longadu, Sukurchhari and Muralipara in Rangamati district of Chittagong Hill Tracts (CHTs). Soil analyses showed that fungal and bacterial population, microbial respiration and active microbial biomass, maximum water holding capacity, conductivity and moisture contents were significantly (at least $p{\leq}0.05$) lower in shifting cultivated soil compared to adjacent mixed tree plantations at all the sites. On an average in soils of 5 different shifting cultivated lands fungal population was $1.33{\times}10^5$ CFU/g dry soil and bacterial population $1.80{\times}10^7$ CFU/g dry soil and in mixed plantations fungal population was $1.70{\times}10^5$ and bacterial population $2.51{\times}10^7$ CFU/g dry soil. Organic matter and exchangeable Ca and Mg contents were significantly (at least $p{\leq}0.05$) lower and bulk density significantly (at least $p{\leq}0.05$) higher in shifting cultivated land in most of the locations compared to adjacent mixed tree plantations. Ratios of microbial respiration and organic carbon as well as active microbial biomass and organic carbon were distinctly lower and pH higher at 3 locations in shifting cultivated soils compared to mixed plantations. Findings of various soil properties, therefore, suggest that shifting cultivation has deteriorating effects on soil environment.

• Journal of Forest and Environmental Science
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• v.30 no.4
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• pp.370-377
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• 2014

There are very few studies about soil chemical and biological properties under tropical dry evergreen forest Coromandel Coast, India. The present study was conducted in six tropical dry evergreen forests sites such as Oorani, Puthupet, Vadaagram, Kotthatai, Sendrakillai and Palvathunnan. We measured the quantity of soil chemical, biological properties and selected soil microorganisms for investigating the impacts of soil microbial populations on soil chemical and biological properties. The result showed that total N, P, Ca, S, Fe, Mn, Cu, Co, exchangeable K, Olson P, extractable Ca and phosphobacterial population were higher in the soil from Kothattai forest site. Organic carbon, total Mg, extractable Na, soil respiration, ${\beta}$-glucosidase activity, bacterial population, fungi population and actinomycetes population were higher in the soil from Palvathunn forest site. Total K, $NH_4{^+}$-N, $NO_3{^-}$-N, exchangeable K, extractable Ca, extractable Na, azotobacter population, bacillus population and rhizobacteria population were higher in the soil from Sendrakillai. Beijerinckia population, rhizobacteria and soluble sodium were higher in Puthupet forest soil. Total Si, total Na and exchangeable K were higher in soil from Oorani forest site. Total Mo and exchangeable K were higher in the soil from Vadaagaram forest site. The results showed that organic carbon, total N, $NH_4{^+}$-N, $NO_3{^-}$-N, extractable P, extractable Ca, soil respiration and ${\beta}$-glucosidase were significantly correlated with soil microbial populations. Therefore soil microorganisms are important factor for maintaining soil quality in tropical dry evergreen forest.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1083-1095
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• 2019

Butyrate is known to play a significant role in energy metabolism and regulating genomic activities that influence rumen nutrition utilization and function. Thus, this study investigated the effects of an isolated butyrate-producing bacteria, Clostridium saccharobutylicum, in rumen butyrate production, fermentation parameters and microbial population in Holstein-Friesian cow. An isolated butyrate-producing bacterium from the ruminal fluid of a Holstein-Friesian cow was identified and characterized as Clostridium saccharobutylicum RNAL841125 using 16S rRNA gene sequencing and phylogenetic analyses. The bacterium was evaluated on its effects as supplement on in vitro rumen fermentation and microbial population. Supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum increased (p < 0.05) microbial crude protein, butyrate and total volatile fatty acids concentration but had no significant effect on $NH_3-N$ at 24 h incubation. Butyrate and total VFA concentrations were higher (p < 0.05) in supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum compared with control, with no differences observed for total gas production, $NH_3-N$ and propionate concentration. However, as the inclusion rate (CFU/ml) of C. saccharobutylicum was increased, reduction of rumen fermentation values was observed. Furthermore, butyrate-producing bacteria and Fibrobacter succinogenes population in the rumen increased in response with supplementation of C. saccharobutylicum, while no differences in the population in total bacteria, protozoa and fungi were observed among treatments. Overall, our study suggests that supplementation with $10^6CFU/ml$ C. saccharobutylicum has the potential to improve ruminal fermentation through increased concentrations of butyrate and total volatile fatty acid, and enhanced population of butyrate-producing bacteria and cellulolytic bacteria F. succinogenes.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.8-16
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• 2001

This experiment was conducted to investigate the effects on plant growth, soil chemical properties and microbial flora with microbial fertilizer to chinese cabbage cultivation. The plant growth was promoted and the yield increased by application of Tian Li Bao(TLB) microbial fertilizer as compared with the control. However, yield a littler decreased in case of the reduced amount of urea application as a top dressing and half of compost chicken manure as a basial fertilizer even if treated with TLB microbial fertilizer. Organic matter and total nitrogen contents decreased as compared to those in the control, and total nitrogen ranged in 0.76~1.44% in the treatments at harvesting time, and decreased with application of TLB microbial fertilizer compared to that of the control. The available phosphorus content in the field before experiment was 559ppm, but it was 755ppm and 653 in the control and treatments at harvesting time, respectively. Therefore, it was shown that phosphorus content in the treatment was lower than that of the control. On the other hand, total nitrogen, phosphorous and K ranged from 2.62 to 2.94%, from 1.48 to 1.55% and from 3.60 to 4.38% in plants after harvest, respectively. There were no significant differences among the treatments. For the soil microbial flora, the population of bacteria in the treatments decreased with application of microbial fertilizer as compared with the control over all cultivation periods. It was shown that the population of pseudomonas spp. was over 3 times higher than that of the control after harvesting. The population of actinomycetes didn't show difference among the treatments, but high density of fungi after harvesting were observed in the treatments.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.186-186
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• 2005

• Journal of Korean Society of Environmental Engineers
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• v.32 no.4
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• pp.369-378
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• 2010

Microorganisms are key-role player for stabilization of landfill sites. In order to evaluate the availability of T-RFLP(Terminal Restriction Fragment Length Polymorphism) for monitoring microbial community variations during stabilization of landfill sites, the phylogenic diversity of microbial community in the leachate from 4 different full-scale landfills was characterized by T-RFLP based on bacterial 16S rDNA. Main population of microbial community analyzed by T-RFLP was significantly similar with that of microbial community analyzed by clone library analysis. The results of T-RFLP analysis for main population of microbial community in the leachate from landfills with different landfill structures, waste types and landfill ages showed apparently different microbial diversity and structures. Therefore, long-term monitoring of microbial community in leachate from landfill sites by using T-RFLP is expected to be available for evaluation of landfill stability.

• The Plant Pathology Journal
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• v.18 no.1
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• pp.30-35
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• 2002

The hyphal growth and biocontrol efficacy of Trichodemo harzianum in soil may depend on its interactions with biotic components of the soil environment. The effect of soil microbial biomass on growth and biocontrol efficacy of T. hanianum isolate ThzIDl-M3 (green fluorescent protein transformant) was investigated using artificially prepared different levels of soil microbial biomass (153,328, or 517ug biomass carbon per g of dry soil; BC). The hyphal growth of T. harzanum was significantly inhibited in the soil with 328 or 517 $\mu$g BC compared with 153 ug BC. When ThzIDl-M3 was added to the soils as an alginate pellet formulation, the recoverable population of ThzIDl-M3 varied, but the highest population occurred in 517ug BC. Addition of alginate pellets of ThzIDl-M3 to the soils (10 per 50 g) resulted in increased indigenous microbial populations (total fungi, bacterial fluorescent Pseudomonas app., and actinomycetes). Furthermore, colonizing ability of ThzIDl-M3 on sclerotia of Sclerotinia sclerotiorum was significantly reduced in the soil with high revel of BC. These results suggest that increased soil microbial biomass contributes to increased interactions between introduced T. harzianum and soil microorganisms, consequently reducing the biocontrol efficacy of 1T. harzianum.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.363-369
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• 2010

This study was conducted to investigate the effects of different sanitizers and contact times on storage quality and microbial growth in fresh-cut broccoli. Fresh broccoli samples were cut into small pieces, washed each for 90 s and 180 s in normal tap water (TW), $100\;{\mu}/l$ chlorinated water (CL, pH 7), electrolyzed water (EW, pH 7.2) containing $100\;{\mu}/l$ free chlorine, or $2\;{\mu}/l$ ozonated water ($O_3$). Then, samples were packaged in 30-${\mu}m$ polyethylene bags and stored at $5^{\circ}C$ for 9 days. No significant differences were observed in gas composition and color parameters ($L^*$, $a^*$, $b^*$, and hue angle) among different sanitizers with contact times. No off-odor was detected during the storage. A longer contact time was not effective in reducing microbial population, except with $O_3$ washing. $O_3$ with 90 s was not much effective in reducing microbial population compared with Cl or EW. However, samples washed with $O_3$ for 180 s observed the lowest numbers of total aerobic and coliform plate counts. The result suggested that, a longer contact time of ozone can be used as a potential sanitizer to maintain the microbial quality and safety of fresh-cut broccoli.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.236-241
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• 2011

Soil microbial diversity was responsible for a strong effect on the chemical properties of orchard soils. This study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in orchard soils in Gyeongnam Province. The average nutrients in the orchard soils were 2.6 times for available phosphorous, 2.3 times for exchangeable potassium and 1.3 times for exchangeable calcium higher compared to recommend concentrations in the orchard soils. Contents of available phosphorous and organic matter in the inclined piedmont soils were higher than those in the other topographical soils (p<0.05). Populations of fungi and fluorescence Pseudomonas sp. in the silt loam soils were significantly higher than those in the sandy loam soils (p<0.05). In principal component analysis of chemical properties and microbial populations in the upland soils, our findings suggested that population of bacteria should be considered as potential factor responsible for the clear orchard soils differentiation. The soil organic matter was significantly negative correlation with population of bacteria whereas was positive correlation with population of fungi in orchard soils.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.819-823
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• 2011

The present study evaluated the seasonal changes of the soil microbial population by selected media in an organic farming system (OFS) with rye rotation cropping management compared to those in a conventional farming system (CFS) with chemical fertilizers, pesticide and herbicide from May 2009 to October 2010 in an upland field. With the exception of fungi, populations of aerobic bacteria, Gram-negative bacteria, and Bacillus spp. were higher in the OFS soil during soybean-growing stages. In addition, populations of aerobic bacteria, Gram-negative bacteria, and Bacillus spp. in the OFS soil were nearly two times more than those in the CFS soil on reproductive growth stages. Our findings suggested that Bacillus spp. should be considered as responsible factor for microbial population differentiation observed between the OFS and the CFS in upland fields.