Research Fellow
Ph.D., M.S. Plant Pathology Washington State University
B.S. Plant Pathology National Taiwan University
Tel¡G+886-2-2787-1050 (Lab) E-mail¡Gyumingju@gate.sinica.edu.tw
Research Interests Studies of the Xylariaceae¡XMonographic and mycobiotic studies; molecular phylogeny
Xylariaceae belongs to Pyrenomycetes, an fungal class characterized by unitunicate asci and flask-shaped ascomata, and is among the most commonly encountered groups of fungi in Ascomycota. This important family includes approximately 50 genera, a great portion of which are poorly understood in biological context. Members of the family are characterized by conspicuous stromata, an ascal apical ring staining blue in an iodine solution, and brown ascospores possessing a germination slit. Most are inhabitants of wood, seeds, fruits, or leaves of angiosperms; a few are found on gymnosperms or tree ferns. Some are associated with insect nests. Most decay wood and many are plant pathogens. Many studies on endophytes manifest that xylariaceous fungi are isolated from living plant tissues in high frequencies. Xylariaceous fungi are encountered throughout the world but have higher diversities in the tropical and subtropical regions. Indeed, the contemporary activity in biodiversity has led to extensive and intensive collecting of these fungi in the tropics and subtropics, many of which cannot be identified and almost none of which are understood in a biological context.
I. World and regional studies of the Xylariaceae We have been involved in monographing or revising a number of xylariaceous genera, including: Amphirosellinia, Annulohypoxylon, Ascovirgaria, Biscogniauxia, Creosphaeria, Daldinia, Discoxylaria, Entoleuca, Hypoxylon, Jumillera, Kretzschmaria, Kretzschmariella, Nemania, Occultitheca, Paramphisphaeria, Stilbohypoxylon, Theissenia, Vivantia, Whalleya, and Xylotumulus. Our Xylariaceae website http://mycology.sinica.edu.tw/Xylariaceae covers many of these genera. Like many regions in the tropics and subtropics, Taiwan harbors a great number of xylariaceous fungi: 17 genera¡XAnnulohypoxylon, Anthostomella, Biscogniauxia, Collodiscula, Creosphaeria, Daldinia, Halorosellinia, Hypoxylon, Jumillera, Kretzschmaria, Nemania, Rhopalostroma, Rosellinia, Stilbohypoxylon, Theissenia, Whalleya, and Xylaria¡Xand nearly 200 species are known.
II. Molecular phylogeny of the Xylariaceae We have employed sequences of various DNA loci to infer the relationships among taxonomic groups of the Xylariaceae. One of our recent studies analyzed ß-tubulin and £\-actin sequences from 83 representative species of Annulohypoxylon, Biscogniauxia, Daldinia, and Hypoxylon. In brief, while Biscogniauxia, Annulohypoxylon, and Hypoxylon formed three well-supported clades, Daldinia formed a subclade within Hypoxylon and made the latter a paraphyletic genus. Another recent study was to infer the phylogenetic position of Theissenia, which had been questioned as to whether or not it belongs to Xylariaceae due primarily to its lack of ascal apical rings and to the absence of germ slits in ascospores of the type species T. pyrenocrata. Our analyses confirmed the xylariaceous nature of Theissenia and placed the genus in the subfamily Hypoxyloideae among the genera characterized by bipartite stromata.
Figure 1. Stromata of four xylariaceous genera. (A) Annulohypoxylon. (B) Biscogniauxia. (C) Daldinia; inset shows a stromatal vertical section with concentric zone lines. (D) Hypoxylon.
Figure 2. Theissenia rogersii. (A) Stroma on bark. (B) Young ascus and ascospores stained pinkish with acid fuschin. (C) Ascospores in various developmental stages. (D) A diagrammatic representation showing vertical section of stroma. (E) Enlargement of the circled area in (D) showing the stromatal surface partially fractured away.
Ju, Y.-M., and Hsieh, H.-M. (2007). Xylaria species associated with nests of Odontotermes formosanus in Taiwan. Mycologia (in press).
Ju, Y.-M., Hsieh, H.-M., Ho, M.-C., Szu, D.-H., and Fang, M.-J. (2007). Theissenia rogersii sp. nov. and phylogenetic position of Theissenia. Mycologia 99: 612-621.
Bitzer, J., Kopcke, B., Stadler, M., Hellwig, V., Ju, Y.-M., Seip, S., and Henkel, T. (2007). Accelerated dereplication of natural products, supported by reference libraries. Chimia 61: 332-338.
Guu, J.-R., Ju, Y.-M., and Hsieh, H.-J. (2007). Nectriaceous fungi collected from forests in Taiwan. Botanical Studies 48: 187-203.
Ju, Y.-M., Juang, S.-H., Chen, K.-J., and Lee, T.-H. (2007). TMC-151 A Monoacetate, a new polyketide from Bionectria ochroleuca. Zeitschrift fur Naturforschung 62b: 561-564.
Rogers, J. D., Ju, Y.- M., and Hemmes, D. E. (2006). Hypoxylon subdisciforme sp. nov., Nemania abortiva sp. nov., and Xylotumulus gibbisporus gen. et sp. nov. from Hawaii, Hawaiian Islands. Sydowia 58: 290-299.
Hsieh, H.-M., Ju, Y.-M., and Rogers, J. D. (2005). Molecular phylogeny of Hypoxylon and closely related genera. Mycologia 97: 914-923.
Rogers, J. D., Ju, Y.-M., and Lehmann, J. (2005). Some Xylaria species on termite nests. Mycologia 97: 844-865.
Ju, Y.-M., Rogers, J. D., and Hsieh, H.-M. (2005). New Hypoxylon and Nemania species from Costa Rica and Taiwan. Mycologia 97: 562-567.
Hellwig, V., Ju, Y.-M., Rogers, J. D., Fournier, J., and Stadler, M. (2005). Hypomiltin, a novel azaphilone from Hypoxylon hypomiltum, and chemotypes in Hypoxylon sect. Hypoxylon as inferred from analytical HPLC profiling. Mycological Progress 4: 39-54.
Ju, Y.-M., Rogers, J. D., and Hsieh, H.-M. (2004). Amphirosellinia gen. nov. and a new species of Entoleuca. Mycologia 96: 1393-1402.
Yang, P., Fu, H., Walker, J., Papa, C. M., Smalle, J., Ju, Y.-M., and Vierstra, R. D. (2004). Purification of the Arabidopsis 26S proteasome. Journal of Biological Chemistry 279: 6401-6413.
Stadler, M., Ju, Y.-M., and Rogers, J. D. (2004). Chemotaxonomy of Entonaema, Rhopalostroma and other Xylariaceae. Mycological Research 108: 239-256.
Rogers, J. D., and Ju, Y.-M. (2004). Kretzschmaria varians sp. nov., Xylaria coremiifera sp. nov. and Xylaria umbonata sp. nov. from Costa Rica. Mycological Progress 3: 37-40.
Fernandez, F. A., Rogers, J. D., Ju, Y.-M., Huhndorf, S. M., and Umana, L. (2004). Paramphisphaeria costaricensis gen. et sp. nov. and Pachytrype rimosa sp. nov. from Costa Rica. Mycologia 96: 175-179.
Ju, Y.-M., Rogers, J. D., and Hsieh, H.-M. (2004). New Hypoxylon species and notes on some names associated with or related to Hypoxylon. Mycologia 96: 154-161.
Rogers, J. D., and Ju, Y.-M. (2003). Occultitheca costaricensis gen. et sp. nov. and Apiocamarops pulvinata sp. nov. from Costa Rica. Sydowia 55: 359-364.
Rogers, J. D., Hemmes, D. E., and Ju, Y.-M. (2003). Xylaria kaumanae sp. nov. from the Island of Hawaii (Hawaii, USA). Sydowia 55: 104-108.
Ju, Y.-M., Rogers, J. D., and Hsieh, H.-M. (2003). The genus Theissenia: T. pyrenocrata, T. cinerea sp. nov., and T. eurima sp. nov. Mycologia 95: 109-116.
