• The Korean Journal of Mycology
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• v.21 no.3
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• pp.188-194
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• 1993

Anastomosis types and hyphal interactions in culture among different location and field isolates of Rhizoctonia solani AG-1(IA), R. oryzae and R. oryzae-sativae were examined. In the pairings of R. solani AG-1(IA) isolates, cytoplasmic fusion only occurred in the self-anastomoses, and non-cytoplasmic fusion occurred in the other combinations. In the pairings of R. oryzae isolates, cytoplasmic fusion occurred in six combinations between different location isolates and in two combinations between different field isolates from the same locations as well as in the self-anastomoses. In that case, four isolates of the fungus reciprocally made the cytoplasmic fusion. In the pairings of R. oryzae-sativae isolates, only non-cytoplasmic fusion occurred among the different location and field isolates, in which cytoplasmic fusion also occurred in the self-anastomoses. When non-cytoplasmic fusion isolates(NCFIs) of R. solani AG-1(IA) were opposed on PDA, a killing zone developed between the NCFls paired after incubation. The killing zone also developed between the NCFls of R. oryzae paired. No killing zone developed between the cytoplasmic fusion isolates(CFIs) of R. oryzae, in which mycelia of the CFIs intermingled with each other without formation of any demarcation line. An entangled zone instead of the killing zone developed between the NCFIs of R. oryzae-sativae.

• Asian Journal of Turfgrass Science
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• v.6 no.2
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• pp.89-98
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• 1992

Cultural characteristics and pathogenicity on the isolates of Rhizoctonia oryzae, R. oryzae-sativae and anastomosis group of R. solani and evaluation of selected fungicides on brown patch disease of creeping bentgrass and large patch disease of zoysia grass were studied comparatively. From effect of temperature on the rate of mycelia growth, the result indicated that the temperature groups were separated into four types : isolates of R. oryzae and R. oryzae-sativae had an optimum temperature of $30~35^{\circ}C$. Anastomosis groups of R. solani were separated into three temperature types as followings : high temperature type had an optimum temperature from 25 to $30^{\circ}C$, moderate type had grown from 20 to $25^{\circ}C$ for optimum and low temperature type had an optimum temperature of $20^{\circ}C$ but at $35^{\circ}C$ did not grow. Inoculation tests showed that AG-1( I A), AG-1( I B), bentgrass isolate of R. solani and R. oryzae were strongly pathogenic on creeping bentgrass, followed by AG-2-1, AG-4, AG-5 and AG-2-2 isolates of R. solani moderately to weakly. Zoysia grass isolate of R. solani and R. oryzae were strongly pathogenic on zoysia grass but AG-1( I B) and AG-5 isolates of R. solani showed moderately pathogenic. Capro(iprodione oxine-copper) and mytan(myclobutanil) were extremely effective against brown patch disease of creeping bentgrass and large patch disease of zoysia grass followed by thiopan (thiopanate-methyl) and pencycuron for brown patch disease and tolos(tolclofos-methyl) and thiopan for large patch disease.

• Mycobiology
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• v.43 no.4
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• pp.415-422
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• 2015

The study aimed to evaluate the probiotic properties, antioxidant activity and fermentative capacity of Acremonium charticola and Rhizopus oryzae isolated from the Indonesian fermented dried cassava, with particular application on poultry. A. charticola inhibited the growth of Escherichia coli and Aspergillus flavus. A. charticola and R. oryzae grew in potato dextrose agar (PDA) adjusted to pH 3 and 8 or in PDA supplemented with bile salt up to 0.8%. After soaking for 8 hr, the survival rate of A. charticola in the simulated gastric juice (pH 2) and bile solutions (2% bile salt) was lower than that of R. oryzae. A. charticola and R. oryzae exhibited strong antioxidant activities. Compared to unfermented cassava pulp (control), the fibre content of cassava pulp tended to be lower after fermentation with A. charticola for 14 days. The populations of A. charticola and R. oryzae were significantly higher in fermented cassava pulp than in unfermented one. Coliform was higher in cassava pulp fermented with R. oryzae or A. charticola + R. oryzae compared to control after 7 days of fermentation, however, the bacteria were not different between A. charticola-fermented cassava pulp and control. Lactic acid bacteria (LAB) were higher in A. charticola- and R. oryzae-fermented cassava pulp than those in control, however, no difference of LAB was observed between A. charticola + R. oryzae-fermented cassava pulp and control. In conclusion, A. charticola exhibited antibacterial, antifungal and antioxidant activity, gastrointestinal persistence and fermentative capacity that may be beneficial for poultry industry.

• Korean Journal of Microbiology
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• v.31 no.3
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• pp.218-223
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• 1993

Conditions for the release and regeneration of protoplasts form Rhizopus oryzae and intergeneric protoplast fusion between Rhizopus oryzae and Aspergillus oryzae were studied. High yields of protoplast fusion between Rhizopus oryzae and Aspergillus oxyzae were studied. High yield of protoplasts from young germilings of R. oryzae were obtained by using lytic enzymes containing chitosanase (3 mg/ml), chitinase (3 mg/ml) and Novozym 234 (5 mg/ml). 0.5M glucose was used as the osmotic stabilizer and optimum pH of buffer was determined to be pH 7.5-8.0. Under these conditions, protoplasts were formed after about 3-4 hrs incubation. Approximately, 1.0%-4.9% of these protoplasts were formed after about 3-4 hrs incubation. Approximately, 1.0%-4.9% of these protoplasts regenerated on solid medium with a soft agar overlay. We have also carried out protoplasts fusion between R. oryzae and A. oryzae and have succeeded in obtaining three types of intergeneric fusants. In these experiments, 35% PEG-4000 and 10 mM CaCl$_{2}$ were used as fsogenic agents, and auxotrophic properties were used as a genetic marker to select fusants. Complementation frequency be protoplasts fusion of A. oxyzae and R. oryzae was 4.4% * 10$^{-5}$ . The fusant strains of the first type were prototrophs showing an Aspergillus type morphology with dark-yellow sporulation, those of the second type were also Apergillus type morphology but showed no sporulation. And the strains of the third type stopped growing when fusion products grown on regeneration minimal medium were transferred to fresh minimal medium. The formation of fusion products was observed by fluorescent vital stains for complementary labelling of protoplats from R. oryzae and A. oryzae. Rhodamine 6G and fluorescein diacetate wer useful complementary vital stains of Rhizopus and Aspergillus protoplasts for visualization of requency and type (dicell, multicell) of fusion.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.11-20
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• 1996

한 쌍의 R16-1과 R23-2R primer를 이용한 PCR에 의해 증폭된 16S와 23S rDNA 사이의 rDNA spacer 부위의 다형성들이 Pseudomonas avenae, P. glumae, P. fuscovaginae, P. syringae pv. syrngae, Xanthomonas oryzae pv. oryzae, X. oryzae, Xanthomonas herbicola 등 벼 종자전염성 51개 균주의 구분을 위하여 적용되었다. 증폭산물은 820∼950bp의 크기였으며, 각각의 종에 특이적이었고 구분이 가능하였다. Pseudomonas species의 증폭산물은 P. avenae는 950bp, P. glumae는 850bp, P. fuscovaginae는 770pb 및 P. syringae pv. syringae는 1,240, 1,100 및 820bp로 특이적이었다. P. avenae와 P. glumae의 국내균주들은 다형성에 있어 종내 변이는 없었다. X. oryzae pv. oryzae의 860bp와 X. oryzae pv. oryzicola의 890, 440 및 370bp의 이차산물에서 Xanthomonas species의 종내에서 균주에 관련없이 단일화된 다형성을 보였다. CXO 211을 제외한 모든 국내 균주는 a형에 속한 반면 하나의 국내 균주를 포함하여 4개 균주는 b형이었다. E. herbicola의 spacer 부위 증폭은 여러 개의 band를 보였으며, 증폭상은 각각 동일하였고, strain간의 종내 변이는 없었다. 본 실험 결과에 의하여 16S와 23S rDNAdp R16-1과 R23-2R primer를 이용하여 PCR 증폭된 spacer 다형성의 구별은 종자전염성 세균의 신속한 구별에 이용될 수 있을것이다.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.257-265
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• 1995

Morphological characteristics and pathogenicity of Rhizoctonia species causing blight diseases of turfgrasses were studied. The species were identified as Rhizoctonia cerealis Van der Hoeven, R. oryzae Ryker et Gooch, and R. solani $K{\ddot{u}hn}$ based on their morphological and cultural characteristics. Isolates of R. solani were assigned to anastomosis groups (AG) with cultural type 1 (1A), 2-2 (IIIB), and 2-2 (IV). R. cerealis, R. oryzae and R. solani induced sheath rot and foliar blight symptoms on creeping bentgrass (Agrostis palustris) and zoysiagrass (Zoysia japonica). Inoculation tests showed that disease severity with isolates of R. cerealis and R. oryzae were more serious to creeping bentgrass than zoysiagrass. AG 1(1A) isolates of R. solani were strongly pathogenic on creeping bentgrass, but moderate to zoysiagrass. AG 2-2 (III) isolates were moderately pathogenic to zoysiagrass, but weakly to creeping bentgrass. AG 2-2 (IV) isolates from zoysiagrass were moderately pathogenic to zoysiagrass, but weakly to creeping bentgrass.

• The Korean Journal of Mycology
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• v.21 no.1
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• pp.16-22
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• 1993

Morphological and cultural characteristics of fungi causing rice sclerotial diseases were examined. Hyphal widths of R. solani and R. oryzae were same and ranged $6.0-12.0\;{\mu}m$ with average $9.0\;{\mu}m$, the widest among those of the sclerotial fungi examined. Hyphal width of R. oryzae sativae ranged $6.0-9.0{\mu}m$ with average $7.4{\mu}m$. Hyphal width of R. cerealis was the narrowest among those of Rhizoctonia species examined, and the same was hyphal width of S. oryzae among those of Sclerotium species. Nuclear staining by HCL-Giemsa method showed that R. solani and R. oryzae had many nuclei within one hyphal cell, S. oryzae one nucleus, and the other sclerotial fungi mostly two nuclei. The nuclear number of R. solani was the largest, which ranged 2-17 with average 6.3. Average size of sclerotia of the sclerotial fungi except S. hydrophilum and S. oryzae produced in lesions ranged 1.0-2.0mm. Average size of sclerotia of S. hydrophilum and S. oryzae was 0.5mm and 0.24mm, respectively. Sclerotia of R. solani and R. oryzae produced in culture were more variable in size and larger than those produced in lesions. However, the sclerotial sizes of the other sclerotial fungi produced in culture were almost the same as those produced in lesions. Sclerotial colors of sclerotial fungi produced in lesions were similar to those produced in culture, but sclerotial shapes of some sclerotial fungi exhibited somewhat difference between the sclerotia produced in lesions and in culture. Optimum temperature for mycelial growth of R. cerealis was $23^{\circ}C$, and that of the other sclerotial fungi ranged from $27\;to\;33^{\circ}C$. Maximum temperature for mycelial growth of some sclerotial fungi was as high as $41^{\circ}C$, while that of R. cerealis was as low as $31^{\circ}C$. Minimum temperature for mycelial growth of R. cerealis was $2^{\circ}C$, and that of the other sclerotial fungi ranged from $6\;to\;10^{\circ}C$.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.304-309
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• 2014

The rpf genes and $colS_{XOO1207}/colR_{XOO1208}$ were known to require for virulence of Xanthomonas oryzae pv. oryzae (Xoo). In Xoo KACC10331 genome, two more colS/colR genes, $colS_{XOO3534}$ (raxH)/$colR_{XOO3535}$ (raxR) and $colS_{XOO3762}/colR_{XOO3763}$ were annotated. The $colS_{XOO3534}/colR_{XOO3535}$ were known to control AvrXa21 activity and functions of $colS_{XOO3762}/colR_{XOO3763}$ were unknown in Xoo. To characterize the relationship between rpf and colS/colR genes, expression of colS/colR genes in Rpf mutants of Xoo were analyzed with quantitative reverse transcription PCR (qRT-PCR). Expressions of all three colS/colR genes increased in the rpfF mutant in which DSF synthesis is defective. Expression of $colS_{XOO1207}/col-R_{XOO1208}$, $colS_{XOO3534}/colR_{XOO3535}$ and $colS_{XOO3762}/colR_{XOO3763}$ increased 2, 2-7, 3-13 folds respectively. Expression of $colS_{XOO3534}$ and $colS_{XOO3762}$ also increased 2-4 folds in the rpfG mutant in which the signal from DSF is no longer transferred to down-stream. Expression of the other colS/colR genes was not significantly changed in the rpfG mutant compared to the wild type. Since RpfF and RpfG are responsible for DSF synthesis and signal transfer from DSF to down-stream to regulate virulence gene expression, these results suggest that the DSF and DSF-mediated signal regulate negatively three colS/colR genes in Xoo.

• Mycobiology
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• v.38 no.4
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• pp.336-338
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• 2010

Rhizopus oryzae is reported for the first time on Cucumis melo L. var. makuwa Makino. A detailed description of this Korean specimen is given, along with its rDNA internal transcribed spacer sequence. On the basis of mycological characteristics and molecular data, the fungus was identified as R. oryzae Went & Prinsen Geerligs.

• Food Science and Preservation
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• v.21 no.4
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• pp.573-580
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• 2014

The enzymatic activity of Nuruk and the quality properties of Yakju were investigated according to different fungi. The fungi that were used in this study were Aspergillus kawachii KCCM 32819, Aspergillus niger KCCM 32005, Rhizopus japonicus KCCM 11604, Rhizopus oryzae KCCM 11272, Rhizopus oryzae KCCM 11273, Rhizopus oryzae KCCM 11276, and Mucor rouxii KCCM 60148. The study results are as follows. The saccharogenic power of Rhizopus oryzae KCCM 11272 Nuruk was the highest (3,647.72 SP/g) among all the samples. The ${\alpha}$-amylase production and protease activities were highest (3.76 DU and 4.7 tyrosine mg/min, respectively) in the Rhizopus japonicus KCCM 11604 Nuruk. The pH levels of the Yakju made with commercial Nuruk and Rhizopus japonicus KCCM 11604 Nuruk were 4.14 and 4.07, respectively. The total titratable acid content of the Yakju made with Rhizopus oryzae KCCM 11273 Nuruk was the highest (0.56%) among all the samples. Rhizopus japonicus KCCM 11604 and Rhizopus oryzae KCCM 11272 had the highest ethanol yields (15.18% and 15.10%, respectively). In the sensory evaluation carried out in this study, the panel preferred the Yakju made with Rhizopus japonicus KCCM 11604 Nuruk. Overall, however, the panel did not like the Yakju made with Aspergillus niger KCCM 32005 Nuruk.