Root Age-Dependent Changes in Arbuscular Mycorrhizal Fungal Communities Colonizing Roots of Panax ginseng

In this study, we examined arbuscular mycorrhizal fungal (AMF) community structure colonizing field-cultivated ginseng roots according of different ages, such as 1- to 5-year-old plant, collected from Geumsan-gun, Korea. A total of seven AMF species namely, Funnelliformis caledonium, F. moseae, Gigaspora margarita, Paraglomus laccatum, P. occultum, Rhizophagus irregularis, and Scutellospora heterogama were identified from the roots using cloning, PCR-restriction fragment length polymorphism and sequence analysis of the large subunit region in rDNA. AMF species diversity in the ginseng roots decreased with the increase in root age because of the decreased species evenness. In addition, the community structures of AMF in the roots became more uniform. These results suggest that the age of ginseng affects mycorrhizal colonization and its community structure.

Mariannaea samuelsii Isolated from a Bark Beetle-Infested Elm Tree in Korea

During an investigation of fungi from an elm tree infested with bark beetles in Korea, one isolate, DUCC401, was isolated from elm wood. Based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer and 28S rDNA (large subunit) sequences, the isolate, DUCC401, was identified as Mariannaea samuelsii. Mycelia of the fungus grew faster on malt extract agar than on potato dextrose agar and oatmeal agar media. Temperature and pH for optimal growth of fungal mycelia were 25degrees C and pH 7.0, respectively. The fungus demonstrated the capacity to degrade cellobiose, starch, and xylan. This is the first report on isolation of Mariannaea samuelsii in Korea.

Two Species of Endophytic Penicillium from Pinus rigida in Korea

Upon studying the diversity of fungal endophytes associated with pine trees in Korea, many species of Penicillium were encountered. In this study, we report two species of Penicillium isolated from the needles of Pinus rigida. Based on ID region analysis, cultural and morphological characteristics, the two species were identified as Penicillium fellutanum and P. toxicarium, both of which are new to Korea.

Sequence Analysis of rDNA-LSU Gene of Orientobilharzia turkestanicum from Mainland of China / 中国寄生虫学与寄生虫病杂志

Objective To classify the taxonomic status of O.cheni in relation to O.turkestanicum var. tuberculata from the mainland of China by comparing their nucleotide sequences of nuclear ribosomal partial large subunit gene (LSU). Methods The genomic DNA of adult worms were extracted by the GNT-K method. The target gene was amplified by PCR using specific primers. The PCR products were purified before ligation into the plasmid PCR-blunt (Invitrogen). Recombinant plasmids were amplified in E.coli , extracted and purified using routine methods and then sequenced using M13 primers (F/R) on a Licor long-read auto-sequencer. Sequences of O. turkestanicum was retrieved from GenBank and aligned with our data in BioEdit. Results The nucleotide sequences of LSU between O.turkestanicum var. tuberculata and O.cheni was 100% identical, and 99.99% identical between O.turkestanicum var. tuberculata and O.turkestanicum . Conclusion This study demonstrated high similarity in LSU nucleotide sequences, and the results do not support O.cheni as an independent species. O.cheni may be a synonym of O.turkestanicum var. tuberculata , and O.turkestanicum var. tuberculata is probably also a synonym of O.turkestanicum .