• Microbiology and Biotechnology Letters
• /
• v.19 no.2
• /
• pp.140-146
• /
• 1991

Mutation experiments were performed to select the mutant of Aspergillus niger 55, which had lost almost all the ability to produce transglucosidases but retained that of high productivity of raw meal saccharifying enzyme, by means of successive induction with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), ultraviolet(UV) light, and ${\gamma}$-rays. Also, we used the mutant enrichment techniques, such as liquid culture-filtration procedure and differential heat sensitivity of conidia, in order to increase the possibility of obtaining a mutant. The glucoamylase productivity of mutant PFST-38 was 11 times higher than that of the parent strain. The mutant PFST-38 was morphologically identical to the parent strain, except for the size of conidia, the tendency to form conidia and the lenght of conidiophore. Asp. niger mutant PFST-38 apeared to be useful for the submerged production of the raw corn meal saccharifying enzyme.

• Research in Plant Disease
• /
• v.19 no.4
• /
• pp.308-312
• /
• 2013

The popcorn disease caused by sclerotia forming fungi reduces the productivity of mulberry fruits in world wide. In Korea, only two species (Ciboria shiraiana and Scleromitrula shiraiana) have been reported as the major causal organisms and their morphological features are also largely unknown. Hereby, we report the first identification of another species (i.e. Ciboria carunculoides) in Korea and detailed features of their anamorphic stage. Fungi dominantly associated with sclerotia were purely isolated from infected mulberry fruits under the microscope. PCR-amplified DNA encoding 5.8S rRNA displayed 100% similarity to Ciboria carunculoides. The anamorphic features exhibited the absence of true mycelia. Instead, very short, aseptated, branched conidiophores were directly emerged from sclerotia. Phialides were usually three in number from each conidiophore, ampuliform to navicular in shape, slightly curved and tapering towards the apex. Conidia were produced from phialides and mostly found as one celled, pear shaped, not hyaline with smooth to uneven surface walled. Diversely modified features in phialides formed pseudo-mycelial structures around the host tissue. Combined all, current study is the first report of C. carunculoides isolated in Korea and the foremost detailed description of its anamorph stage.

• The Korean Journal of Mycology
• /
• v.8 no.3
• /
• pp.159-166
• /
• 1980

Aspergillus niger van Tieghem was cultured by the method of submerged and synchronized culture for the study of differentiation. Acid-phenol soluble cell proteins of the fungus were extracted from four stages during development. Those acid-phenol soluble proteins were separated by polyacrylamide gel electrophoresis to determine the protein patterns. A new protein band was observed from the pre-sporulation body, color density of the stained protein bands in four tubes differed according to the differentiation stages. The number of protein bands in 10% gels varied from 18 to 16, 17, and 19 according to the course of spore germination stage, conidiophore stage, phialide maturation stage and sporulation stage.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.729-732
• /
• 2000

Antifungal activities of domestic plants were examined to develop natural anti-microbial agents, able to protect onion from spoiling microorganisms during their storage. A fungus was isolated from spoiling onion and identified to Penicillium sp. ON-211, based on the morphological characteristics of conidiophore and conidia. Chloroform extracts of Juniperus chinesis Linnaeus, Juniperus. chi. var. horizontalis, water extract of Thujs orientalis Linnaeus' seed and the n-hexane extract of Juniperus. chi. var. horizontalis N. showed remarkable antifungal activties against this fungus.

• Korean Journal Plant Pathology
• /
• v.14 no.6
• /
• pp.642-645
• /
• 1998

A severe pink mold rot on matured melon fruits occurred under a glass tunnel cultivation in Chinju at Kyeongasngnam-do Agricultural Research and Extention Services on May of 1998. Basal portion of the fruits toward blossom end was preferably infected and colonized by the fungus. The causal fungus consistently isolated from the lesions was identified as Trichothecium roseum based on following mycological characteristics. Conidia were hyaline or brightly colored, 2-celled, ovoid or elipsoid, characteristically held together zi-zag chains. Conidiophore was long, slender, simple, septate, bearing conidia-meristem arthrospores-apically, singly when young and successively by slight growth of conidiphore apex. Optimum temperature for mycelial growth and conidial germination was recorded at 20~$25^{\circ}C$. However, over 48% of the fungal conidia were germinated at 15$^{\circ}C$ and mycelial growth was only slightly slower than $25^{\circ}C$. The temperature profiles and high humidity available during the cultivation were considered favorable for the pathogen as showing 22% infection rate on matured melon fruits cv. Saros. This is the first report of pink mold rot of melon caused by T. roseum in Korea.

• The Plant Pathology Journal
• /
• v.16 no.3
• /
• pp.147-150
• /
• 2000

Sporulation patterns of rice blast fungus were studied at relatively later stages of leaf blast and neck blast seasons in Icheon, Korea. This experiment was done by detaching lesion-bearing leaves and panicle bases. The number of conidia remaining on the leaf blast lesions of different cultivars from Jul 20 to Jul 23 ranged from 3,640 to 82,740 spores. More conidia were observed on the adaxial surface because they were released from abaxial surface. After heading, sporulation was observed from the lesions on the flag leaves but the number of spores was less than in the late July. Detached panicle bases or uppermost internodes infected by Pyricularia grisea produced abundant amount of conidia. Among these panicle bases, 30.1 mm size lesion recorded the highest count of 244,560 spores. When we compared the sporulation amount using the KY-type spore trap, more conidia were recorded from intact lesions than from the lesions which removed conidia and conidiophore The ratio of conidia release against total sporulation ranged from 20.5%-25.0% for leaf blast and 8.2%-25.3% in the neck blast. Effective inoculum potential was also discussed.

• The Korean Journal of Mycology
• /
• v.13 no.2
• /
• pp.65-74
• /
• 1985

Aspergillus niger IMI 41873 was cultured by the method of synchronous and submerged culture. Its sporulation occurred in the culture. Ribonucleic acids were extracted at each stage of life cycle. These RNAs were digested, separated and determined by P.E.I. cellulose TLC and HPLC methods. The levels of ribonucleic acids in sporulating mycelia were higher than those of conidiophore and phialide forming mycelia. Inosine 5-monophosphate and adenosine 5-monophosphate derivatives were found in HPLC separations. The levels of inosine 5-monophosphate and adenosine 5-monophosphate derivatives per ribonucleic acid were constant through differentiation. After the standard purine necleosides and boiling water extracts from A. bisporus, F. velutipes and L. edodes were added into the culture, their effects on sporulation were examined. Sporulation was greatly enhanced in each adding experiment.

• The Korean Journal of Mycology
• /
• v.26 no.3 s.86
• /
• pp.399-402
• /
• 1998

An entomopathogenic fungus, Zoophthora radicans, was found causing epizootics in populations of the green peach aphid, Myzus persicae, on March 27, 1998 at Seongju Gun, Kyungbuk Province in Korea. Anamorhic characteristics of the fungus were described using light and scanning electron microscopy. Distinguishing characteristics of Z. radicans is formation of capilliconidia on a single slender secondary conidiophore.

• The Korean Journal of Mycology
• /
• v.47 no.1
• /
• pp.29-34
• /
• 2019

A fungal isolate designated 17E029 was isolated from a soil sample in Jeju, Korea. The strain was similar to other Allantophomopsiella species in its morphological characteristics such as grey mycelia, conidiophore, and conidia sizes. The isolate produced aerial mycelia, which appeared grey on the reverse side of the media surfaces and turned black on the front side of the colonies. The conidiophores emanating from the hyphae were hyaline, grey, aseptate, branched, and $6.7{\sim}9.2{\times}1.8{\sim}2.5{\mu}m$. Conidiogenous cells were ovoid to subcylindrical, discrete, guttulate, and hyaline. Conidia were hyaline, aseptate, smooth, guttulate, oval to subcylindrical, irregular in shape, and $6.0{\sim}7.8{\times}3.0{\sim}3.4{\mu}m$. The strain was confirmed based on phylogenetic analysis of the closest related organism, A. pseudotsugae CBS 288.37, using the partial 28S, internal transcribed spacer rDNA regions, and partial RNA polymerase II second largest subunit locus (RPB2) gene sequences along with its culture characteristics. Therefore, morphological observations and phylogenetic analysis revealed that strain 17E029 is similar to the previously identified A. pseudotsugae. Hence, this species was described as A. pseudotsugae strain 17E029, which is a new record in Korea.

• The Korean Journal of Mycology
• /
• v.29 no.1
• /
• pp.75-78
• /
• 2001

The powdery mildew of Statice (Limonium shinuatum) extensively occurred in the experimental farm of Changwon Floricultural Experiment Station, Kyongsangnam-do Agricultural Research and Extension Services in 2000. Both sides of the leaves, petioles and stems were covered with the white fungal spores and mycelia, and then the leaves, petioles and stems became dark-colored, eventually died. The conidia and conidiophores formed on the lesion were observed. Conidia were cylindric to ellipsoid, $25.3{\sim}49.4{\times}12.3{\sim}7.2{\mu}m$ in size and borne singly on conidiophore. Fibrosin bodies were not observed. Conidiophores were stright with 2-4 cylindric cells, and $65.7{\sim}124.8{\mu}m$ in size. Appressorium was lobed type. Cleistothecia were not formed. This is the first report on powdery mildew of Statice (Limonium shinuatum) caused by Oidium sp. in Korea.