Introduction to Distribution and Ecology of Sterile Conks of Inonotus obliquus

Inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. This fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (Betula spp). The dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. Chaga are a folk remedy in Russia, reflecting the circumboreal distribution of I. obliquus in boreal forest ecosystems on Betula spp. and in meridional mountain forests on beech (Fagus spp.) in Russia, Scandinavia, Central Europe, and Eastern Europe. Distribution at lower latitudes in Western and Southern Europe, Northern America, Asia, Japan, and Korea is rare. Infected trees grow for many years without several symptoms of decline. The infection can penetrate through stem injuries with exterior sterile conks developing later. In the Czech Republic, cinder conk is found on birches inhabiting peat bogs and in mountain areas with a colder and more humid climate, although it is widespread in other broad leaved species over the Czech Republic. The most common hosts are B. pendula, B. pubescens, B. carpatica, and F. sylvatica. Less frequent hosts include Acer campestre, Acer pseudoplatanus, Alnus glutinosa, Alnus incana, Fraxinus excelsior, Quercus cerris, Q. petraea, Q. robur, Q. delachampii, and Ulmus sp.

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 +/- 1degrees 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.

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 25degrees C in the dark condition until the mycelia 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 +/- 1degrees 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.

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

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.