Ju-Ri Woo

Cadophora malorum Cs‐8‐1 as a new fungal strain producing gibberellins isolated from Calystegia soldanella

Fourteen endophytic fungi with different colony morphologies were isolated from the roots of Calystegia soldanella. Endophytic fungi isolated from C. soldanella were identified by internal transcribed spacer (ITS) region. To verify plant growth promotion (PGP), culture filtrates of isolated endophytic fungi were treated in Waito‐c rice (WR) and C. soldanella seedlings. Culture filtrates of Cs‐8‐1 fungal strain had advanced PGP activity. The presence of physiologically bioactive gibberellins (GA) GA1 (1.213 ng ml−1), GA3 (1.292 ng ml−1), GA4 (3.6 ng ml−1), GA7 (1.328 ng ml−1), other inactive GA9 (0.796 ng ml−1) and GA12 (0.417 ng ml−1), GA20 (0.302 ng ml−1), GA24 (1.351 ng ml−1), GA34 (0.076 ng ml−1), and GA53 (0.051 ng ml−1) in culture filtrates of Cs‐8‐1 fungal strain was detected. The Cs‐8‐1 fungal strain was confirmed as a producer of GAs. Molecular analysis of sequences showed high similarity of 99% to Cadophora malorum. Consequentially, the Cs‐8‐1 fungal strain was identified as a new C. malorum producing GAs.

Diversity and Plant Growth-Promotion of Endophytic Fungi Isolated from the Roots of Plants in Dokdo Islands

Endophytic fungi were isolated from the roots of plants growing naturally on the island of Dokdo. Plant samples, such as Miscanthus sinensis, Achyranthus japonica and Echinochloa crusgali were isolated from Dongdo, and those such as Honkenya peploides and Artemsia koidzumii were isolated from Seodo. Twenty one strains of endophytic fungi were isolated from these plants. To identify the strains, PCR (polymerase chain reaction) amplification of the partial ITS (Internal Transcribed Spacer) regions was done with universal primers ITS-1 and ITS-4 to determine the nucleotide sequence of the ITS regions. Of the strains isolated from Miscanthus sinensis, 75% were Penicillium sp. and 25% were Aspergillus sp. Fifty five percent of strains isolated from Achyranthus japonica were Penicillium sp., 30% were Aspergillus sp. and 15% were Zygorhynchus sp. Strains isolated from Echinochloa crusgali were Penicillium sp. (50%), Aspergillus sp. (12%), Giberella sp. (13%), Talaromyces sp. (9%) and Umbelopsis sp. (8%). Of the strains isolated from Honkenya peploides, 76% were Penicillium sp. and 24% were Pestalotiopsis sp. Strains isolated from Artemisia koidzumii were Penicillium sp. (81%) and Mucor sp. (19%). As a result of bioassay, Ec-3-1 strain isolated from Echinochloa crusgalli showed plant growth-promotion activity. Of all the endophytic fungi isolated, Penicillium sp. was the most abundantly distributed fungal strain in all plants used in this study.

Diversity of Endophytic Fungi from the Roots of Halophytes Growing in Go-chang Salt Marsh

Halophyte samples, such as Suaeda japonica, Phragmites australis, Limonium tetragonum, Suaeda maritima were collected from Go-chang salt marsh. Thirty-nine endophytic fungal strains were isolated from the roots of halophytes naturally growing in salt marsh. All endophytic fungal strains isolated were analyzed by internal transcribed spacer (ITS) containing ITS1, 5.8 s and ITS2 region. Endophytic fungal strains belong to eight orders, i.e., Eurotiales (36%), Pleosporales (26%), Hypocreales (18%), Incertae sedis (8%), Glomerellales (5%), Sordariales (2%), Xylariales (2%), and Capnodiales (3%). On genus level, they were composed of Alternaria, Aspergillus, Chaetomium, Cladosporium, Colletotrichum, Coniothyrium, Dothideomycete, Fusarium, Gibberella, Macrophoma, Penicillium, Pestalotiopsis, Phaeosphaeria, Phoma, Pleosporales, Pseudozyma, Talaromyces, and Termitomyces. Of them, Penicillium (26%), Fusarium (13%) of Eurotiales and Hypocreales were predominant.

Diversity and Characteristics of Rhizosphere Microorganisms Isolated from the Soil around the Roots of Three Plants Native to the Dokdo Islands

Three plant species, Aster sphathulifolius, Sedum oryzifolium, and Lysimachia mauritiana, native to the Dokdo Islands in South Korea, were examined for rhizosphere microorganisms by using 16S rDNA sequences. Nine species of rhizosphere microorganisms were isolated from the three native plant species, respectively. Phylogenetic analysis showed that the microorganisms could be classified into 19 species belonging to four phyla (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria), and the characteristics of the microbes were confirmed. Rhizosphere microorganisms from the six orders (Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, Oceanospirillales, and Rhodobacterales) were isolated from S. oryzifolium. From L. mauritiana, microbes belonging to the seven orders (Bacillales, Flavobacteriales, Micrococcales, Oceanospirillales, Rhizobiales, and Rhodobacterales) were isolated. From A. sphathulifolius, the six orders of rhizosphere microorganisms (Alteromonadales, Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, and Rhizobiales) were isolated. These data showed that Actinobacteria and Proteobacteria were the dominant phyla for the rhizosphere of all three plants. To confirm the bacterial diversity in rhizospheres, Shannon’s diversity index (H’) was used at the genus level. In these data, the rhizosphere from S. oryzifolium and L. mauritiana had more diverse bacteria compared to that from A. sphathulifolius.Three plant species, Aster sphathulifolius, Sedum oryzifolium, and Lysimachia mauritiana, native to the Dokdo Islands in South Korea, were examined for rhizosphere microorganisms by using 16S rDNA sequences. Nine species of rhizosphere microorganisms were isolated from the three native plant species, respectively. Phylogenetic analysis showed that the microorganisms could be classified into 19 species belonging to four phyla (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria), and the characteristics of the microbes were confirmed. Rhizosphere microorganisms from the six orders (Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, Oceanospirillales, and Rhodobacterales) were isolated from S. oryzifolium. From L. mauritiana, microbes belonging to the seven orders (Bacillales, Flavobacteriales, Micrococcales, Oceanospirillales, Rhizobiales, and Rhodobacterales) were isolated. From A. sphathulifolius, the six orders of rhizosphere microorganisms (Alteromonadales, Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, and Rhizobiales) were isolated. These data showed that Actinobacteria and Proteobacteria were the dominant phyla for the rhizosphere of all three plants. To confirm the bacterial diversity in rhizospheres, Shannon’s diversity index (H’) was used at the genus level. In these data, the rhizosphere from S. oryzifolium and L. mauritiana had more diverse bacteria compared to that from A. sphathulifolius.

Genetic Diversity of Endophytic Fungi Isolated from the Roots of Halophytes Naturally Growing in Suncheon Bay

Endophytic fungi were isolated from the roots of halophytes, Suaeda japonica and Carex scabrifolia in the Suncheonbay. The ITS region in rDNA of 15 endophytic fungal strains were amplified using PCR with universal primers ITS1 and ITS4, and those amplified fragments were sequenced. Based on ITS sequence, five fungal genera were identified in S. japonica and seven fungal genera were identified in C. scabrifolia. The Shannon`s diversity index (H`) of endophytic fungi isolated from S. japonica and C. scabrifolia was 1.561 and 1.889, respectively. In phylogenetic analysis, it was shown that Ascomycota and Pezizomycotina was widely distributed both in S. japonica and C. scabrifolia. Also, Sordariomycetes, Dothideomycetes and Eurotiomycetes were shown to be distributed in these halophytes used in this experiment.

Plant Growth-Promoting Activity of Endophytic Fungi Isolated from the Roots of Native Plants in Dokdo Islands

독도에 자생하고 있는 6 종류의 식물뿌리로부터 내생균을 분리하였다. 동도에서 갯제비쑥, 명아주, 까마중과 서도에서 도깨비쇠고비, 술패랭이 그리고 번행초를 연구재료로 사용하였다. 총 32 종의 내생균을 분리하였고, universal primers ITS1과 ITS4를 사용하여 ITS 영역을 PCR로 증폭하여 동정하였다. 염기서열 분석결과, 6 종류의 식물의 뿌리에서 모두 32종류의 다양한 내생균류를 분리 및 동정 할 수 있었다. 독도 자생식물인 갯제비쑥 4종, 명아주 8종, 까마중 3종, 도깨비쇠고비 3종, 술패랭이 3종, 번행초 11종의 내생균이 분리되었다. 내생균들의 배양여액은 식물생장촉진활성을 확인하기 위하여 난장이벼의 유묘에 처리되었다. 그 결과, 명아주에서 분리된 Ca-5-2-2 균주가 우수하게 식물생장촉진활성을 나타내었다. 그리고 독도에 자생하는 6종류의 식물에서 Penicillium sp.와 Fusarium sp. 그리고 Aspergillus sp.의 내생균이 가장 많이 존재함을 알 수 있었다. 【Endophytic fungal strains were isolated from the roots of six species plants in the Dokdo islands. Native plant samples, such as Artemisia japonica, Chenopodium album and Solanum nigrum were isolated from Dongdo, and those such as Cyrtomium falcatum, Dianthus longicalyx and Tetragonia tetragonoides were isolated from Seodo. In total, thirty two fungal strains were isolated from these native plants. To identify the fungal strains, polymerase chain reaction (PCR) amplification of internal transcribed spacer (ITS: containing ITS1, 5.8s and ITS2 region) regions was done with universal primers ITS1 and ITS4. Endophytic fungi of four species were isolated from A. japonica, eight species from C. album, three species from S. nigrum, three species from C. falcatum, three species from D. longicalyx and eleven species from T. tetragonoides. Culture filtrates (CF) of isolated endophytic fungi were used to treatwaito-c rice seedlings to test plant growth-promoting activity. As a result of bioassay, Ca-5-2-2 strain isolated from C. album expressed highest plant growth-promotion activity. Of all the endophytic fungi isolated, Penicillium sp., Fusarium sp. and Aspergillus sp. were the most abundantly distributed fungal strains in the six plants used in this study.】

Diversity of Endophytic Fungi Isolated from the Rootlet of Pinus densiflora Colonized by Tricholoma matsutake

Endophytic fungi were isolated from the Pinus densiflora rootlet colonized by ectomycorrhizal fungus Tricholoma matsutake. Eighteen species of endophytic fungi were identified by analyzing rDNA-ITS sequence. As the result of the rDNA-ITS analysis, ascomycota of 15 species and Mucoromycotina of 3 species were isolated. Of all the endophytic fungi isolated, Penicillium sp. was confirmed as the highest frequency.

Comparison of Endo-, Exo-Cellular Enzyme Activity for New Strains of Hypsizygus marmoreus

This study was carried out to investigate the morphological and physiological characteristics of six new cultivars of Hypsizygus marmoreus (Hm) and measure endo-, exo-cellular enzyme-specific activity. The domestic wild stain (Hm3-10) and commercial strain in Japan (Hm1-1) were mated by crossing monokaryon mycelia. We gained 58 strains from one of 400 crosses through the cultivation experiment, and selected six strains from one of 58 strains through the cultivation experiment. When six of the selected new strains were grown during several spawn culture periods (60, 70, 80, 90, and 100 days), a spawn culture period of more 80 days was considered to be excellent as being shorter than 19~20 days. Therefore, we determined the period of spawn culture as 80 days. Three strains such as Hm15-3, Hm15-4, and Hm17-5 showed an excellent result. When endo-cellular enzyme activity measured eight strains, we obtained a result of that specific activity of -amylase at the highest as 73.9~102.2 unit/mg protein, and chitinase is lower than -amylase at 8.1~13.1 unit/mg protein. When exo-cellular enzyme activity measured eight strains, we determined the result of that specific activity of -amylase is the highest at 5,292~1,184 unit/mg protein, and CMCase and xylanase were 1,140~245 unit/mg protein, 94~575 unit/mg protein, compared to each other. However, the enzyme activity of -glucosidase and chitinase is low.

Secondary Structure of the Ribosomal Internal Transcribed Spacer (ITS) Region of Hypsizygus marmoreus

The ribosomal DNA (rDNA) clusters of Hypsizygus marmoreus 3-10 and H. marmoreus 1-1 were analyzed in this study. The small subunit (SSU) and intergenic spacer 2 (IGS 2) was partially sequenced. The internal transcribed spacer 1 (ITS 1), 5.8S, internal transcribed spacer 2 (ITS 2), large subunit (LSU), intergenic spacer 1 (IGS 1), and 5S were completely sequenced. The rDNA clusters of H. marmoreus 3-10 and H. marmoreus 1-1 were 7,049 bp in length. The sequence of SSU rDNA, which corresponded to 18S rDNA, was 1,796 bp in length, and the sequence of LSU rDNA, which corresponded to 28S rDNA, was 3,348 bp in length. The ITS region that variable region and IGS region that nontranscribed spacer was 462 bp and 1,290 bp in length. The sequence of 5.8S rDNA and 5S rDNA was 153 bp and 43 bp in length, respectively. The 17 bp of the rDNA cluster in the H. marmoreus 3-10 strain was different to that in the H. marmoreus 1-1 strain, with 2 bp in the SSU, 3 bp in the ITS, 9 bp in the LSU, and 3 bp in the IGS. The analysis of the secondary structure revealed that the ITS regions of H. marmoreus 3-10 and H. marmoreus 1-1 have five stem-loop structures. Interestingly, among these structures, one different nucleotide sequence resulted in a different secondary structure in stem-loop V.

A Phylogenetic Relationship between Foreign and Korean Strains of Flammulina velutipes Identified by rDNA-ITS Sequence Analysis

This study was carried out to investigate the genetic relationship of Flammulina velutipes with other species. The ribosomal DNA cluster containing 4 rRNA genes from F. velutipes 4154 were sequenced. The length of the rDNA cluster sequence was estimated at 7,403 bp long and consisted of 1,806 bp of SSU rDNA, 245 bp of ITS 1 region, 159 bp of 5.8S rDNA, 308 bp of ITS 2 region, 3,402 bp of LSU rDNA, 1,400 bp of IGS 1 region, and 83 bp of 5S rDNA. The F. velutipes 4154 genes were contained in the rDNA cluster of F. velutipes in the order of SSU rDNA - ITS 1 - 5.8S rDNA - ITS 2 - LSU rDNA - IGS 1 - 5S rDNA. The phylogenetic relationships of 20 strains of Tricholomataceae and Physalacriaceae were analyzed by conducting distance analysis using the Neighbor-joining (NJ) method. The 20 strains used in this study were divided into three groups and the strains of the genus Flammulina were related very closely to strains of Physalacria bambusae.