• The Korean Journal of Mycology
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• v.22 no.2
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• pp.190-195
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• 1994

Studies were conducted to determine the potential of sodium hypochlorite(SHC) on the control of bacterial yellow blotch in cultivated oyster mushroom, Pleurotus ostreatus. SHC at the concentration of 80 ppm was effective on the control of Pseudomonas agarici causing yellow blotch in oyster mushroom except number 916 isolate. In vitro the mycelial growth was slightly inhibited at the concentration higher than 100 ppm of sodium hypochlorite, but retardation of the mycelial growth was soon recovered. Spray of SHC solution at the concentration of 40-50 ppm per day significantly reduced the incidence of the yellow blotch without impairing the growth of oyster mushroom in field culture. However, the higher concentration of SHC(67 ppm) induced yellow brown or dark gray in color and deformed cap and elongated stripe in morphology of fruiting body. Results indicate that periodical spray of sodium hypochlorite seems to be the recommendable method for protection against bacterial yellow blotch disease in oyster mushroom without reducing food quality.

• The Korean Journal of Mycology
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• v.45 no.4
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• pp.370-376
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• 2017

Pseudomonads cause bacterial brown blotch disease, which causes great damage to the common mushroom Agaricus bisporus. The tolerance of A. bisporus to pseudomonads was tested and found to not be correlated with mycelium growth ability. The offsprings of the tolerant strain (ASI1085) to pseudomonads were not as tolerant as their parents in the mycelium stage. But, tolerance decreased compared to mycelium in the fruiting body. The offsprings of the weakly tolerant strain (ASI1321) were even more weak in the mycelium stage. It is presumed that the tolerance of the parents is transferred to later generations. The tolerance in the mycelium was not correlated in the fruiting body. Therefore, the browning of the fruiting body is thought to be induced by other factors. Pseudomonas tolaasii caused higher browning than Pseudomonas agarici. Pseudomonas reactans did not have a significant effect on the mycelium, but affected the browning of the fruit bodies. P. agarici had higher ability to inhibit mycelium growth than fruiting body growth.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.310-315
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• 2015

Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.1
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• pp.96-126
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• 2002

In the course of screening natural extracts for hair growth, we found that the extract of dried root of Sophora flavescens has the prominent hair growth promoting effect. After topical application of Sophora flavescens extract to the back of C57BL/6 mice, the earlier conversion of telogen-to-anagen phase was induced. In addition, the Sophora flavescens extract revealed to possess potent inhibitory effect on $5{\alpha}$-reductase Ⅰ and Ⅱ activity. The growth of dermal papilla cells and mouse vibrissae hair follicle cultured in vitro, however, was not affected by Sophora flavescens extract treatment. RT-PCR analysis showed that Sophora flavescens extract induced mRNA levels of growth factors such as insulin-like growth factor-Ⅰ and keratinocyte growth factor in dermal papilla cells, suggesting hair growth promoting effect of Sophora flavescens extract is mediated through inhibition of $5{\alpha}$-reductase type Ⅱ activity and the regulation of growth factors in dermal papilla cells. Furthermore, Sophora flavescens extract also showed anti-bacterial effect on Propionibacterium acnes. These results suggest that Sophora flavescens can be used as a potent treatment agent for helping hair growth stimulation and acne inhibition.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.235-239
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• 1977

The experiments were contucted to investigate the variability of pathogenesity, growth amount and UV-sensitibity on the streptomycin resistant isolate of the rice bacterial leaf blight pathogen, Xanthomonas oryzae, which selected by the stepwise transfer in 100, 3,000 and 10,000 ug/ml Argepto contained media. And the results obtained were as follows. (1) The SM-resistant isolates were tested the pathogenesity on the differential variety of rice, wase-Aikoku-3, Rant Emas-2, Hwang ok, and Kimmase. And the SM resistant isolate, obtained from 75-6 isolate, showed the reaction of moderately resistant to the differential variety of Hwang ok instead of susceptible reaction with its parental isolate. (2) The growth amount of the SM-resistant isolate was slightly higher than that of parental isolate, on the normal media. And the growth was inhibited on the 100ug/ml Agrepto contained media until 60 hours after transfer, however, its growth exceeded than parental isolate in the normal media, after 70 hours of transfer. (3) It is considered that the resistance factor might be stable character, since the sensitivity to UV irradiation (with 254 mr wave length) of the resistant isolate was the same as that of its parental isolate.

• The Plant Pathology Journal
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• v.33 no.2
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• pp.170-183
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• 2017

Bacterial fruit blotch (BFB), which is caused by Acidovorax citrulli, is a serious threat to watermelon growers around the world. The present study was conducted to screen effective rhizobacterial isolates against 35 different A. citrulli isolates and determine their efficacy on BFB and growth parameters of watermelon. Two rhizobacterial isolates viz. Paenibacillus polymyxa (SN-22), Sinomonas atrocyanea (NSB-27) showed high inhibitory activity in the preliminary screening and were further evaluated for their effect on BFB and growth parameters of three different watermelon varieties under greenhouse conditions. The greenhouse experiment result revealed that SN-22 and NSB-27 significantly reduced BFB and had significant stimulatory effect on total chlorophyll content, plant height, total fresh weight and total dry weight compared to uninoculated plants across the tested three watermelon varieties. Analysis of the 16S ribosomal RNA (rRNA) sequences revealed that strains SN-22 belong to P. polymyxa and NSB-27 to S. atrocyanea with the bootstrap value of 99% and 98%, respectively. The isolates SN-22 and NSB-27 were tested for antagonistic and PGP traits. The result showed that the tested isolates produced siderophore, hydrolytic enzymes (protease and cellulose), chitinase, starch hydrolytic enzymes and they showed phosphate as well as zinc solubilizing capacity. This is the first report of P. polymyxa (SN-22) and S. atrocyanea (NSB-27) as biocontrol-plant growth promoting rhizobacteria on watermelon.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.69-73
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• 2018

Oak mushroom (Lentinus edodes) is cultivated by using oak logs and sawdust medium. Green mold (Trichoderma) infection on these media severely suppresses the growth of oak mushroom. Usages of antibiotics and chemicals are not generally allowed to control of green mold since the mushroom is a fresh food. Tolaasin and its analogues, peptide toxins secreted by Pseudomonas tolaasii, have the antifungal activity and they have been successful to control the green mold disease. When the green mold, Trichoderma harzianum H1, was cultured in the presence of these toxins, the growth of fungus was effectively suppressed. In sawdust media, when the bacterial culture supernatants were sprayed on the aerial hyphae of green molds, the fungal growth was completely suppressed. Particularly, the antifungal activity was greatly increased by the combined culture extracts of P. tolaasii 6264 and HK11 strains. Therefore, these bacterial strains and their peptide toxins were able to suppress the growth of green molds and these can be good candidates to prevent from Trichoderma disease in oak mushroom cultivation.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.672-676
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• 2003

Effect of a surfactant Tween 80 on the bacterial growth in the rumen was examined on the in vitro pure cultures of Streptococcus bovis, Selenomonas ruminantium, Butyrivibrio fibrisolvens, Prevotella ruminicola, Megasphaera elsidenni, Fibrobacta succinogenes, Ruminanococcus albus and Ruminococcus flavefaciens. Dry matter degradability (DMD), concentrations and compositions of volatile fatty acids (VFA), and the most probable number (MPN) of cellulolytic bacteria and total number of bacteria in the presence of Tween 80 were also examined on the in vitro rumen mixed culture either with barley grain or orchardgrass hay. The growth of S. bovis, S. ruminantium, B. fibrisolvens, P. ruminicola, M. elsidenni and F. succinogenes were significantly higher (p<0.05) at over 0.05% concentrations of Tween 80 than those of the control cultures, while was not changed with R. albus and R. flavefaciens. With rumen mixed culture the DMD of barley grain and orchardgrass hay was significantly higher (p<0.05) at a 0.2% concentration of Tween 80 than the control, being reflected in the significantly higher (p<0.05) VFA production (mmol $g^{-1}$DDM) with orchardgrass hay. The higher (p<0.05) ratio of propionate to acetate at a 0.2% concentration of Tween 80 was also observed with orchardgrass hay, showing a similar trend with barley grain. No changes in the total bacterial number and MPN of cellulolytic bacteria were observed.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.318-326
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• 2016

Two phosphate solubilizing bacteria, Pantoea rodasii PSB-11and Enterobacter aerogenes PSB-12, were isolated from button mushroom compost and employed to assess their synergistic effect in liquid medium and on growth of green gram plants by single and co-inoculation of the strains. Co-inoculation of two strains was found to release the highest content of soluble phosphorus ($521{\mu}g\;ml^{-1}$) into the medium, followed by single inoculation of Pantoea strain ($485{\mu}g\;ml^{-1}$) and Enterobacter strain ($470{\mu}g\;ml^{-1}$). However, there was no significant difference between single inoculation of bacterial strain and co-inoculation of two bacterial strains in terms of phosphorous release. The highest pH reduction, organic acid production and glucose consumption was observed in the E. aerogenes PSB-12 single inoculated culture medium rather than those of co-inoculation. According to the plant growth promotion bioassay, co-inoculated mung bean seedlings recorded 10.6% and 10.7% higher shoot and root growth respectively compared to the control. Therefore, in concluding, co-inoculation of the strains P. rodasii and E. aerogenes displayed better performance in stimulating plant growth than inoculation of each strain alone. However, being short assessment period of the present study, we recommend in engaging further works under field conditions in order to test the suitability of the strains to be used as bio-inoculants.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.208-217
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• 2018

In this study, samples were collected from the leaves and stems of healthy wild Pistachio trees (Pistacia atlantica L.) from various locations of Baneh and Marivan regions, Iran. In total, 61 endophytic bacteria were isolated and grouped according to phenotypic properties. Ten selected isolates from each group were further identified by partial sequencing of the 16S rRNA gene. Based on the results, isolates were identified as bacteria belonging to Pseudomonas, Stenotrophomonas, Bacillus, Pantoea and Serratia genus. The ability of these isolates was evaluated to phytohormone production such as auxin and gibberellin, siderophore production, phosphate solubilization, atmospheric nitrogen fixation, protease and hydrogen cyanide production. All strains were able to produce the plant growth hormone auxin and gibberellin in different amounts. The majority of strains were able to solubilize phosphate. The results of atmospheric nitrogen fixation ability, protease and siderophore production were varied among strains. Only Ba66 could produce a low amount of hydrogen cyanide. The results of biocontrol assay showed that Pb78 and Sp15 strains had the highest and lowest inhibition effects on bacterial plant pathogens, Pseudomonas syringae pv. syringae Pss20 and Pseudomonas tolaasii Pt18 under in vitro condition. Pb3, Pb24 and Pb71 strains significantly promote root formation on carrot slices. To our knowledge this is the first report of the isolation of endophytic bacterial strains belonging to Pantoea, Bacillus, Pseudomonas, Serratia and Stenotrophomonas genus from wild pistachio trees with plant growth promoting potential and biocontrol activity.