Jae-Ouk Shim

Seed Germination of Gastrodia elata Using Symbiotic Fungi, Mycena osmundicola.

The germination rate and longevity of seeds of Gastrodia elata Blume have been observed for 48 weeks using Mycena osmundicola strain H-21, one of fungi stimulating seed germination. Storage condition of post-harvest seeds was observed in the different temperature ranges of -30°C, -5°C, 5°C and 30°C for 48 weeks. After storage period of 48 weeks, the germination rate of G elata was 65.7% at 5°C and 71.6% at -5°C, respectively. Although the germination rate of G elata was 77.3% for 11 weeks at 25°C, the germination rate had been decreased gradually to 49.3% at 13 weeks, 0.3% at 23 weeks and then 0% at 25 weeks. The germination rate was reached to the level of 10% for 2 weeks at -30°C and then decreased to 0%.

The Optimal Culture Conditions for the Mycelial Growth of Oudemansiella radicata

Oudemansiella radicata, one of edible mushrooms belonging to Trieholomataeeae of Basidiomyeota, has been known to exhibit outstanding therapeutic effects on the hypertension caused by high blood pressure and inhibitory effects on the sarcoma 180 and Erhrlieh carcinoma of mice. As one of preliminary experiments for producing fruiting-body of O. radicata, this study was carried out to obtain the basic information for culture conditions of mycelial growth of the fungus. The optimal temperature and pH for the mycelial growth were 25°C and pH 6, respectively. The medium for favorable mycelial growth of O. radicata was shown in the Lilly medium, whereas compact mycelial density was found in Hamada medium. The carbon and nitrogen sources promoting for mycelial growth of O. radicata were xylose and alanine, respectively. The optimum C/N ratio was about 20:1 in ease that 3% glucose was supplimented to the basal medium as a carbon source.

Sawdust Media Affecting the Mycelial Growth and the Fruiting Body Formation of Sparassis crispa

Abstract Six strains of Sparassis crispa such as S. crispa DUM-01, DUM-02, DUM-03, DUM-04, DUM-05, and DUM-06 were tested for their mycelial growth on 6 different kinds of sawdust media and primordial formation on 10 different compositions of larch sawdust media. The highest mycelial growth was recorded on the larch sawdust. Of the 6 strains of S. crispa, S. crispa DUM-04 recorded the favorable formation of primordia. The primordial formation of S. crispa DUM-04 was more favorable on L-3 medium than 9 kinds of larch sawdust media. When S. crispa DUM-04 was cultured on the media of larch sawdust + pine sawdust, the formation of its fruiting bodies was more outstanding on the media of larch sawdust + pine sawdust than those of larch sawdust.

The Fruiting Body Formation of Armillaria mellea on Oak Sawdust Medium Covered with Ground Raw Carrots

To produce an artificial fruiting body of Armillaria mellea on the oak sawdust medium, seven strains of A. mellea were used. The top surface of oak sawdust medium covered with ground raw carrot was inoculated with each of 7 strains and cultured for 30 days at 25°C in the dark condition until the myeelia of A. mellea completely colonized the medium from top to bottom. Then, the mycelia which were fully covered on the top surface of the medium were scratched slightly’ with a spatula and filled with tap water for 3 hours. To induce the primordial formation, the 7 strains of A. mellea were transferred to the growth chamber under the illumination (350 lux) of 12 hours and relative humidity of 85 ± 5% in a day and then cultured at 16 ± 1°C. Only A. mellea IUM 949 could form primordia on the sawdust medium, but the other strains did not make primordia at the same condition. The primordia of A. mellea IUM 949 were formed 10 days after complete colonization of the medium and the fruiting bodies were produced 7 days after a primordial formation. The experimental results suggested that IUM 949 strain might be a good candidate for mass production of fruiting bodies of A. mellea.

The Fruiting Body Formation of Oudemansiella radicata in the Sawdust of Oak (Quercus variabilis) Mixed with Rice Bran

To screen additives and their mixed ratio suitable for the mycelial growth and fruiting body formation of Oudemansiella radicata in the oak sawdust, additives such as rice bran, fermented soybean powder and wheat bran were used. Generally, the mycelial growth of O. radicata has been stable on oak sawdust mixed with rice bran of 5~20%. In case that O. radicata was cultured for about 30 days at 22 ± 1°C under the illumination (350 lux) of 12 hours and moisture condition of 90 ± 5%, the primordia have been formed gradually from red-brown crusts covering the surface of oak sawdust media. Based on the experimental results from 9 strains of O. radicata, fruiting bodies were produced widely on oak sawdust medium mixed with rice bran of 5 to 30%. Even though fruiting bodies of O. radicata have been produced well on oak sawdust media mixed with rice bran, fruiting bodies of O. radicata were produced intensively on oak sawdust media mixed with rice bran of 10%. Therefore, this result will provide a basic information for commercial production of fruiting body of wild O. radicata. This result is the first report associated with an artificial fruiting body formation of O. radicata in Korea.

Diversity of Arbuscular Mycorrhizal Fungi in Paekryung and Daecheong Islands

Abstract Twenty species representing five genera of arbuscular mycorrhizal fungi were isolated from twenty-four soil samples of the rhizo- sphere of the family Gramineae in Paekryung and Daecheong islands. A few species such as Glomus invermaius, G. marcrocapus var. marcrocarpus and Scutellospora coralloidea were recorded for the first time in Korea. The number of spores per lOg of soil was in the range of 8-337 in Paekryung and 16-349 in Daecheong island, respectively. The number of species per lOg of soil was 2-8 species in Paekryung and 2-7 species in Daecheong, respectively. Among them, G. macrocarpus var. macrocarpus was the most abundant species in both islands. The species diversity and evenness were almost similar in Paekryung and Daecheong Islands. Based on the host plants in two islands, the species diversity showed the highest value of 1.63 in Ischaemum crassipes, whereas the evenness of species showed the lowest value of 0.35 in Eragrostis ferraginea.

In vitro Effects of Plant Extracts, and Phytohormones on Mycelial Growth of Anthracnose Fungi

Abstract Water extracts of six plants, such as Allium sativum, A. cepa, Zingiber officinale, Platycodon grandiflorum, Oenanthe javanica, and Capsella brusapastoris, were tested in vitro for inhibitory activity against mycelial growth of anthracnose fungi, Colletotrichum gloeosporioides, C. dematium, and C. coccodes. Among the plant extracts, an Allium sativum extract has good inhibitory effects in all the fungi. Four phytohormones namely, IAA (indole-3-acetic acid), NAA (a-Naphthyl acetic acid), 2,4-D (2,4-Dichloro phenoxy acetic acid) and BAP (Benzyl adenine purine) were used to find out the role over mycelial growth of these fungi. All the concentrations of BAP have good inhibitory effect against mycelial growth of these fungi than that of other tested plant hormones.

Morphological Characteristics of Pseudosclerotia of Grifola umbellata in In Vitro

The present study was carried out to investigate morphological characteristics of pseudosclerotia of Grifola umbellata formed by artificial cultures. Isolate G. umbellata DUM GUS-01 was obtained from sclerotium cultivated in field. The fungal isolate was cultured on PDYM broth, PDYMA (potato dextrose yeast malt agar) and oak sawdust media at 20°C under the dark condition. G. umbellata DUM GUS-01 showed a volumetric increment of fungal lumps rather than mycelial growth. Particularly, G. umbellata DUM GUS-01 produced a large amount of melanin pigments in all culture treatments. The color of the fungal mass has been changed into grey gradually, and then formed melanized rind-like structure on its superficial part. The fungal structures which were covered with melanized rind-like layer were named as pseudosclerotia of G. umbellata. The pseudosclerotia of G. umbellata DUM GUS-01 formed a new white mycelial mass, which was swollen out of the melanized rind structure for its volumetric increment. When the pseudosclerotia were sectioned, their structure was discriminated from two structures such as a melanized rind-like structure layer formed by aggregation of aged mycelia and a white mycelial mass with high density. As results of scanning electron microscopic examination, the pseudosclerotia of G. umbellata DUM GUS-01 which were formed in in vitro conditions were similar to the sclerotia of G. umbellata cultivated in natural conditions except for the crystals formed in medula layer of natural sclerotia. Although size, solidity of rind structure and mycelial compactness of pseudosclerotia were more poor than those of natural sclerotia, the morphological structure and growth pattern of pseudosclerotia were very similar to those of natural sclerotia. Therefore, it is probable to induce pseudosclerotia to sclerotia of G. umbellata in in vitro conditions. Consequently, it seems that the induced pseudosclerotia can be used as inoculum sources to substitute natural sclerotia in field cultivation.