Research activity information

• 1996, 大蔵省印刷局朝陽会賞
  Japan
• 1996, 日本紙パルプ技術協会賞
  Japan

• Role of O-acetyl galactoglucomannan in softwood lignification
  Shoichi Sato; Rikuto Watanabe; Kengo Shigetomi; Yutaka Tamai; Yuji Tsutsumi; Yasumitsu Uraki
  Carbohydrate Polymers, 369, 124303, 124303, Elsevier BV, Dec. 2025, [Peer-reviewed]
  Scientific journal
• Wood properties of Japanese lilac (Syringa reticulata) that promoted selective use in prehistoric Hokkaido
  Ryo Tsuchiya; Yutaka Tamai; Takanobu Sasaki; Yuzou Sano
  Journal of Wood Science, 71, 1, Springer Science and Business Media LLC, 26 May 2025, [Peer-reviewed]
  Scientific journal, Abstract
  
  It is known that in prehistoric Hokkaido, the wood of the Japanese lilac (Syringa reticulata) was used as structural material; for example, in pillars and rafters of dwellings. This suggests that Japanese lilac wood has useful properties, such as high strength and strong decay resistance. However, few studies have been conducted on the wood strength and decay resistance of this species. The present study was undertaken to evaluate the strength and decay resistance of Japanese lilac wood and reveal the factors responsible for its general use in prehistoric periods. The results of mechanical tests show that the strength of the wood, as quantified through several different indices, is above moderate. In particular, static modulus of elasticity and modulus of rupture of Japanese lilac wood were higher than those of other species commonly found in Hokkaido. Regarding decay resistance, the mass-loss rate was only 1.6% after incubation with Trametes versicolor for 60 days. We conclude that Japanese lilac is a suitable material for structural materials in which high bending strength is desired. In addition, its extremely high decay resistance makes it conducive to long-term use outdoors. Overall, the results of this study indicate that the extremely high decay resistance and excellent bending strength of Japanese lilac were the main reasons for its use in prehistoric periods.
• Constitutive chemical defense mechanism of inner bark of Sorbus commixta against Trametes versicolor
  Masato Koyama; Kengo Shigetomi; Yutaka Tamai; Keita Arakawa; Yuzou Sano
  Tree Physiology, 45, 2, Oxford University Press (OUP), 13 Jan. 2025, [Peer-reviewed]
  Scientific journal, Abstract
  
  Tree bark is a crucial tissue that defends tree stems from invasions by microorganisms. However, our understanding of the constitutive chemical defense mechanisms of the tree barks remains limited. Our group recently discovered that the inner bark of Sorbus commixta Hedl. exhibited potent inhibitory effects on the growth of the white-rot fungus, Trametes versicolor (Linnaeus) Lloyd. It was hypothesized that this growth suppression was due to hydrogen cyanide (HCN) originating from cyanogenic glycosides such as amygdalin and prunasin, which are secondary metabolites in the inner bark of S. commixta. To test this hypothesis, we first quantified the amygdalin content in the inner bark of S. commixta and evaluated the antifungal activity (AFA) of HCN against T. versicolor by placing paper discs on potato dextrose agar with T. versicolor. Subsequently, we identified HCN in the inner bark of S. commixta using a picric acid paper. In the AFA tests, the amygdalin + β-glucosidase solution, the potassium cyanide (KCN) + benzaldehyde solution and the KCN solution exhibited elevated AFA against T. versicolor. Conversely, the amygdalin solution, the β-glucosidase solution and the benzaldehyde solution did not exhibit significant AFA. These findings demonstrate that HCN acts as an antifungal agent against T. versicolor. Furthermore, HCN was detected in the freeze-dried inner bark pieces and the trunks of living S. commixta. This suggests that the disruption of the cells in the inner bark of S. commixta caused the cyanogenic glycosides and β-glucosidase to interact, which resulted in the hydrolysis of cyanogenic glycosides and generation of HCN. From the perspective of constitutive chemical defense mechanisms, HCN plays a crucial role in the high AFA of the inner bark of S. commixta against T. versicolor, creating an unfavorable environment for the growth of white-rot fungus after injury breaches the periderm.
• Crude Oil Biodegradation Performance in Natural Seawater of a Trichoderma species from Decaying Mangrove Wood in East Kalimantan
  Sitompul Afrida; Prapti Ira Kumalasari; Jan Friadi Sinaga; Amiruddin; Dede Heri Yuli Yanto; Sakae Horisawa; Yutaka Tamai
  International Journal of Plant & Soil Science, 36, 5, 450, 462, Sciencedomain International, 29 Mar. 2024, [Peer-reviewed]
  Scientific journal, Large-scale petroleum production poses environmental and human health risks, particularly due to petroleum contamination in marine environments. The aim of this study was to isolate and screen fungi inhabiting decaying mangrove wood in East Kalimantan with their ability to degrade crude oil in seawater. In the initial step, fungi were isolated using standard methods and screened for crude oil degradation and biomass production. Selected fungi were based on their significant biomass production. Subsequently, the selected fungus was cultured in three types of media based on natural seawater and crude oil at initial concentrations ranging from 1% to 5% (v/v). The biodegradation of crude oil was assessed spectrophotometrically at 420 nm. Out of the 17 decaying wood fungi, MG-07 exhibited significantly higher biomass production compared to the control medium (without crude oil). Gas chromatography-mass spectrometry analysis indicated that MG-07 degraded 20%–80% of the normal aliphatic compounds in the tested crude oils within 2 weeks. Furthermore, the growth and degradation efficiency of MG-07 was significantly enhanced when cultured in a natural seawater medium containing crude oil, supplemented with glucose (20 g/L) and Tween 80 (1% v/v). The highest observed biomass gains were 867%, with a biodegradation efficiency of 31.6% at a crude oil concentration of 1%. MG-07 was identified as Trichoderma sp. based on the internal transcribed spacer region. The results obtained from this study demonstrate that MG-07 has significant potential for degrading crude oil in saline environments. These findings provide valuable insights for the application of fungi in marine oil spill remediation.
• Isolation, structural elucidation, and biological activity of a novel isocoumarin from the dark septate endophytic fungus Phialocephala fortinii
  Kei Bando; Ryoga Kushibe; Naoki Kitaoka; Yutaka Tamai; Kazuhiko Narisawa; Hideyuki Matsuura
  Zeitschrift für Naturforschung C, 79, 3-4, 89, 92, Walter de Gruyter GmbH, 01 Mar. 2024, [Peer-reviewed]
  Scientific journal, Abstract
  
  A novel isocoumarin was isolated from the mycelia of the dark septate endophytic fungus Phialocephala fortinii. The chemical structure was determined to be 8-hydroxy-6-methoxy-3,7-dimethyl-1H-2-benzopyran-1-one based on mass spectrometry, ¹H-nuclear magnetic resonance (NMR), and ¹³C-NMR spectroscopic analyses, including 2D-NMR experiments. The isolated compound inhibited root growth of Arabidopsis thaliana, suggesting its potential as a plant growth regulator.
• Effect of bone charcoal and ectomycorrhizal fungi on the growth of larch seedlings. -Expectations of trees as grave-marker tree for arboricultural burial-
  KOIKE, Takayoshi; MASUI, Noboru; TAMAI, Yutaka; SASAKI, Keiko; FIJITO, Eishi; ITO, Yuya; WATANABE, Toshihiro; UEDA, Hirofumi
  Technical report for boreal forest conservation of the Hokkaido University Forests, 42, 38, 43, 北海道大学北方生物圏フィールド科学センター森林圏ステーション, 2024
  Japanese, Research institution
• Evaluation of antifungal activities of woody plant barks using an incubation system with Trametes versicolor
  Masato Koyama; Yutaka Tamai; Kengo Shigetomi; Yuzou Sano
  Trees, 38, 1, 37, 47, Springer Science and Business Media LLC, 06 Nov. 2023, [Peer-reviewed]
  Scientific journal
• Aquatic hyphomycete assemblages of Abies sachalinensis leaf litter immersed in a stream in Hokkaido, Japan
  Kohhei Yamamoto; Toshizumi Miyamoto; Akiko Nagasaka; Yu Nagasaka; Yutaka Tamai; Takashi Yajima
  Journal of Forest Research, 29, 2, 137, 143, Informa UK Limited, 12 Oct. 2023, [Peer-reviewed]
  Scientific journal
• Geomyces Species (LC374638), a Fungal Endophyte, Promotes the Growth of Honeysuckle (Lonicera caerulea) through Symbiosis
  Takuya Katsuramoto; Yutaka Tamai; Toshizumi Miyamoto; Takashi Yajima
  International Journal of Plant & Soil Science, 35, 13, 23, 32, Sciencedomain International, 15 May 2023
  Scientific journal, Honeysuckle (Lonicera caerulea), also known as "haskap" in Japan, is a shrub that produces edible berries and inhabits mountainous and wetland areas with harsh environments. In this study, we surveyed the relationship between honeysuckle and the root endophytic fungi. Root samples were collected from the wet land region in Hokkaido, Japan, and subjected to microscopic observation and fungal strain isolation. Totally 47 endophytic fungal strains were isolated from the roots. Inoculation tests showed that a strain of Geomyces sp. promotes the growth of the seedlings and colonizes the epidermal and cortical cells of roots. It suggested that the strain acts as a mycorrhiza-like fungus for the arbuscular mycorrhizal plant. We speculate that honeysuckle establishes a symbiotic relationship with endophytic fungi to overcome acidic and nutrient-deficient environments. This is the first report demonstrating that endophytic ascomycetes promote the growth of host plants belonging to the Caprifoliaceae family.
• Ectomycorrhizal Fungal Communities Associated with Dominant Tree Species in a Subarctic Limestone Area
  Hirotaka Mori; Keisuke Obase; Takashi Yajima; Toshizumi Miyamoto; Yutaka Tamai
  Asian Soil Research Journal, 7, 2, 34, 45, Sciencedomain International, 13 May 2023
  Scientific journal, Limestone soils are stressful for plant growth. Plant-associated ectomycorrhizal (ECM) fungi may promote plant growth under stressful conditions, yet available information on ECM fungi in limestone areas is scarce. We investigated the ECM fungal communities associated with dominant tree species in a subarctic limestone area. We aimed to determine whether the ECM species differed between calcareous and non-calcareous areas, and the distribution property common to ECM fungi in limestone areas. Morphological characterization and DNA sequencing of root tips identified 57 ECM taxa. The ECM fungal compositions in the calcareous area differed from those in the non-calcareous area, even when comparisons were made between fungi on the same tree species. Rather, when ECM species were grouped at the genus level, they tended to be dissimilar between calcareous areas and between non-calcareous areas. Especially, Tomentella spp. and Sebacina spp. tended to be present more frequently in calcareous areas, while Cenococcum geophilum and Russula spp. tended to be present more frequently in non-calcareous areas.
• Effects of bone charcoal and ectomycorrhizal fungi on the growth of Japanese larch seedlings : German natural burial initiative to return burnt bones to the earth at the roots of forests
  Koike, Takayoshi; Ueda, Hirofumi; Koda, Kei'ichi; Kitaoka, Satoshi; Sasaki, Keiko; Fujito, Eishi; Ito, Yuya; Takai, Yutaka; Watanabe, Toshihiro
  Technical report for boreal forest conservation of the Hokkaido University Forests, 41, 16, 20, 北海道大学北方生物圏フィールド科学センター森林圏ステーション, 2023
  Japanese, Research institution
• Single and combined effects of fertilization, ectomycorrhizal inoculation, and drought on container-grown Japanese larch seedlings
  Evgenios Agathokleous; Mitsutoshi Kitao; Masabumi Komatsu; Yutaka Tamai; Hisanori Harayama; Takayoshi Koike
  Journal of Forestry Research, doi.org/10.1007/s11676-022-01565-3, Springer Science and Business Media LLC, 12 Nov. 2022, [Peer-reviewed]
  Scientific journal, Abstract
  
  Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status. Therefore, it is important to enhance the tolerance to drought and thus health, vigor, and success of transplantation seedlings used in the forestry by modifying fertilization and promoting mycorrhization. Here, we sowed seeds of Japanese larch (Larix kaempferi) in 0.2-L containers with 0.5 g (low fertilization; LF) or 2 g (high fertilization; HF) of slow-release fertilizer early in the growing season. One month later, we irrigated seedlings with non-sterilized ectomycorrhizal inoculum (ECM) or sterilized solution (non-ECM), and after about 2 months, plants were either kept well watered (WW; 500 mL water/plant/week) or subjected to drought (DR; 50 mL water per plant/week) until the end of the growing season. HF largely stimulated plant growth and above- and belowground biomass production, effects that are of practical significance, but caused a small decrease in stomatal conductance (Gs₃₉₀) and transpiration rate (E₃₉₀), which in practice is insignificant. ECM treatment resulted in moderate inhibition of seedling growth and biomass and largely canceled out the enhancement of biomass and foliar K content by HF. DR caused a large decrease in CO₂ assimilation, and enhanced stomatal closure and induced senescence. DR also largely depleted foliar Mg and enriched foliar K. Although DR caused a large decrease in foliar P content in LF, it moderately increased P in HF. Likewise, DR increased foliar K in HF but not in LF, and decreased foliar P in ECM plants but not in non-ECM plants. Conversely, ECM plants exhibited a large enrichement in foliar P under WW and had a lower water potential under DR when grown in LF. These results indicate that the drought tolerance and health and vigor of Japanese larch seedlings can be modified by soil fertility and soil microorganisms. This study provides a basis for new multifactorial research programs aimed at producing seedlings of superior quality for forestation under climate change.
• Effects of hemicelluloses on dehydrogenative polymerization of monolignols with cationic cell wall-bound peroxidase
  Yan Lyu; Shiori Suzuki; Hiroki Nagano; Kengo Shigetomi; Yutaka Tamai; Yuji Tsutsumi; Yasumitsu Uraki
  Carbohydrate Polymers, 301, 120305, 120305, Elsevier {BV}, 07 Nov. 2022, [Peer-reviewed]
  English, Scientific journal
• Responses of ectomycorrhizal diversity of larch and its hybrid seedlings and saplings to elevated CO2, O3, and high nitrogen loadin
  QU, Laiye; WANG, Xiaona; MAO, Qiaozhi; AGATHOKLEOUS, Evgenios; CHOI, DongSu; TAMAI, Yutaka; WATANABE, Toshihiro; KOIKE
  Eurasian Journal of Forest Research, 22, 23, 27, May 2022, [Peer-reviewed], [Invited]
  Research institution
• Effects of soil compaction on the seedlings growth and ectomycorrhizal fungal community in hybrid larch
  SUGAI, Tetsuto; YOKOYAMA, Satoko; TAMAI, Yutaka; MORI, Hirotaka; MARCHI, Enrico; WATANABE, Toshihiro; SATOH, Fuyuki; KOIKE, Takayoshi
  Eurasian journal of forest research, 22, 78, 80, 2022
• Phylogenetic placements and cultural characteristics of Tuber species isolated from ectomycorrhizas
  Keisuke Obase; Satoshi Yamanaka; Akihiko Kinoshita; Yutaka Tamai; Takashi Yamanaka
  Mycoscience, 62, 2, 124, 131, 20 Mar. 2021, [Peer-reviewed]
  English, Scientific journal
• Effects of soil nutrient availability and ozone on container-grown Japanese larch seedlings and role of soil microbes
  Evgenios Agathokleous; Mitsutoshi Kitao; Masabumi Komatsu; Yutaka Tamai; Hideyuki Saito; Hisanori Harayama; Akira Uemura; Hiroyuki Tobita; Takayoshi Koike
  Journal of Forestry Research, 31, 6, 2295, 2311, Springer Science and Business Media LLC, Dec. 2020, [Peer-reviewed]
  English, Scientific journal,
  The interactive effects of ozone, soil nutrient availability and root microorganisms on physiological, growth, and productivity traits were studied for the first time for Japanese larch (Larix kaempferi) seedlings grown in containers over a growing season, using a free air ozone-concentration enrichment exposure system. High nutrient availability altered leaf and root nutrient dynamics and enhanced plant growth; however, it also enhanced seedling susceptibility to damping-off disease compared to low nutrient availability. Negative effects of elevated ozone, as compared with ambient ozone, on leaf gas exchange and plant stem form were neither offset nor exacerbated by soil nutrient availability and root colonizers. Such negative effects suggest that elevated ozone may have implications for ecological health even when plant vigor is limited by factors other than ozone. Inoculation of roots with ectomycorrhizae had negligible influence on the effects of either soil nutrient availability or ozone. However, this lack of effect may be upon impeded formation of complete mycorrhizal root tips due to factors other than the manipulated variables. B and Na appeared to have an important role in stress responses, so further studies to examine their link with physiological mechanisms as a function of time. This study provides an important perspective for designing forestry practices to enhance seedling health.
• 2000年に噴火した有珠山の噴出物堆積地における大型菌類の発生消長
  小長谷啓介; 宮本敏澄; 玉井 裕; 矢島 崇
  日本菌学会会報, 61, 2, 81, 90, Nov. 2020, [Peer-reviewed]
  Japanese, Scientific journal
• Evaluating Soil–Root Interaction of Hybrid Larch Seedlings Planted under Soil Compaction and Nitrogen Loading
  Tetsuto Sugai; Satoko Yokoyama; Yutaka Tamai; Hirotaka Mori; Enrico Marchi; Toshihiro Watanabe; Fuyuki Satoh; Takayoshi Koike
  Forests, 11, 9, 947, 947, MDPI AG, 29 Aug. 2020, [Peer-reviewed]
  English, Scientific journal, Although compacted soil can be recovered through root development of planted seedlings, the relationship between root morphologies and soil physical properties remain unclear. We investigated the impacts of soil compaction on planted hybrid larch F1 (Larix gmelinii var. japonica×L. kaempferi, hereafter F1) seedlings with/without N loading. We assumed that N loading might increase the fine root proportion of F1 seedlings under soil compaction, resulting in less effects of root development on soil recovery. We established experimental site with different levels of soil compaction and N loading, where two-year-old F1 seedlings were planted. We used a hardness change index (HCI) to quantify a degree of soil hardness change at each depth. We evaluated root morphological responses to soil compaction and N loading, focusing on ectomycorrhizal symbiosis. High soil hardness reduced the total dry mass of F1 seedlings by more than 30%. Significant positive correlations were found between HCI and root proportion, which indicated that F1 seedling could enhance soil recovery via root development. The reduction of fine root density and its proportion due to soil compaction was observed, while these responses were contrasting under N loading. Nevertheless, the relationships between HCI and root proportion were not changed by N loading. The relative abundance of the larch-specific ectomycorrhizal fungi under soil compaction was increased by N loading. We concluded that the root development of F1 seedling accelerates soil recovery, where N loading could induce root morphological changes under soil compaction, resulting in the persistent relationship between root development and soil recovery.
• Responses of root systems in hybrid larch F₁ seedlings grown under compacted soil
  Sugai Tetsuto; Tamai Yutaka; Koike Takayoshi; Sato Fuyuki; Watanabe Toshihiro
  The Japanese Forest Society Congress, 131, 339, The Japanese Forest Society, 25 May 2020
  Japanese, [in Japanese]
• Effects of biochar and litter on water relations of Japanese black pine (Pinus thunbergii) seedlings
  Saki Fujita; Hanami Watanabe; Vitas Marozas; Yutaka Tamai; Fuyuki Satoh; Takayoshi Koike
  Journal of Forest Research, 25, 2, 76, 82, Informa UK Limited, 03 Mar. 2020, [Peer-reviewed]
  English, Scientific journal
• Tuber spp. isolated from ectomycorrhizal roots of Abies sachalinensis
  Obase K.; Kinoshita A.; Tamai Y.; Yamanaka T.
  Abstracts of Papers Presented at the Meeting of the Mycological Society of Japan, 64, 61, The Mycological Society of Japan, 2020
  Japanese
• Comparison of Mycelial Growth of Different Tricholoma matsutake Strains in Soil Medium at Varying Temperatures
  Maki Narimatsu; Muneyoshi Yamaguchi; Takashi Yamanaka; Seiki Gisusi; Tomonori Azuma; Yutaka Tamai; Tohru Fujita; Masataka Kawai
  Asian Journal of Biotechnology and Bioresource Technology, 5, 1, 8, Sciencedomain International, 20 Nov. 2019, [Peer-reviewed]
  English, Scientific journal, Aims: To investigate the effect of temperature on the mycelial growth of the highly prized mushroom, Tricholoma matsutake, in soil medium.
  Methodology: Seven strains of T. matsutake collected from different areas of Japan were incubated in soil medium at 5, 10, 15, 20, 25, and 30°C for 89 day. After incubation, the linear growth of mycelia from the inoculum was measured on vertical lines under a dissecting microscope and classified by the cultivation day number to obtain the growth rate in each vial. The mycelial densities in the soil medium in all the vials were analyzed using qPCR to determine the mycelial biomass.
  Results: The mycelial growth of T. matsutake strains was mainly observed at 5–25°C. The optimum temperatures for linear mycelial growth and for the increase in mycelial density were 19.6°C and 17.6°C, respectively. These values were lower than those reported previously for T. matsutake grown on agar medium or in liquid medium. These optimum temperatures showed no clear relationship with the mean air temperature at the site of strain collection.
  Conclusion: It can be suggested that a temperature around 18°C is suitable for cultivation of T. matsutake mycelia in the soil medium.
• Investigation of soil environments in the vicinity of Tricholoma matsutake mycelium in Abies sachalinensis stands
  GISUSI Seiki; AZUMA Tomonori; YOSHIDA Shigeichi; YONEYAMA Shozo; HARADA Akira; TSUDA Mayumi; TAMAI Yutaka
  Japanese Journal of Mycology, 60, 2, 43, 48, The Mycological Society of Japan, Nov. 2019, [Peer-reviewed], [Last author]
  Japanese, Scientific journal, To understand the habitat of Tricholoma matsutake in Hokkaido, we investigated the soil environment in an Abies sachalinensis plantation where this fungus colonized. As a result, soil pH and microbial quantity (colony forming unit; cfu) showed lower trend around the colony of T. matsutake than those areas where this fungus was not colonized. In addition, soil temperature was maintained over 0℃ even in the mid-winter despite the minimum air temperature recoded below −20℃, due to snow cover on the forest floor.
• Comparison of the Ability of Several White-rot Fungi to Biobleach Acacia Oxygen-delignified Kraft Pulp
  Sitompul Afrida; Toshihiro Watanabe; Yutaka Tamai
  Asian Journal of Biotechnology and Bioresource Technology, 5, 3, 1, 10, Sciencedomain International, 15 Oct. 2019, [Peer-reviewed], [Corresponding author]
  English, Scientific journal, Previous screening analyses demonstrated that the in vivo biobleaching activities of the white-rot fungi Irpex lacteus KB-1.1 and Lentinus tigrinus LP-7 are higher than those of Phanerochaete chrysosporium and Trametes versicolor. The purpose of the current study was to examine the production of extracellular enzymes of these four white-rot fungi grown on three types of low-cost media containing agricultural and forestry waste, and to evaluate the ability of the produced extracellular enzymes to biobleach Acacia oxygen-delignified kraft pulp (A-OKP). The biobleaching activity of extracellular fractions of I. lacteus, L. tigrinus, T. versicolor, and P. chrysosporium cultures was the most pronounced after 3 days of incubation with Acacia mangium wood powder supplemented with rice bran and 1% glucose (WRBG) with resultant Kappa number reduction of 4.4%, 6.7%, 3.3%, and 3.3%, respectively. Therefore, biobleaching ability of I. lacteus and L. tigrinus have been shown to be higher than of T. versicolor and P. chrysosporium, both in vivo and in vitro.
• Use of DNA sequence data to identify wood-decay fungi likely associated with stem failure caused by windthrow in urban trees during a typhoon
  Yoshie Fukui; Toshizumi Miyamoto; Yutaka Tamai; Akio Koizumi; Takashi Yajima
  Trees, 32, 4, 1147, 1156, Springer Science and Business Media LLC, Aug. 2018, [Peer-reviewed]
  English, Scientific journal
• Effects of simulated nitrogen deposition on ectomycorrhizae community structure in hybrid larch and its parents grown in volcanic ash soil: The role of phosphorous
  Xiaona Wang; Evgenios Agathokleous; Laiye Qu; Saki Fujita; Makoto Watanabe; Yutaka Tamai; Qiaozhi Mao; Akihiro Koyama; Takayoshi Koike
  Science of The Total Environment, 618, 905, 915, Elsevier BV, Mar. 2018, [Peer-reviewed]
  English, Scientific journal
• Changes in the Secondary Xylem of the Living Stem of Four Tree Species in Response to Inoculation with Perenniporia fraxinea
  Mikio Ueta; Chiaki Hori; Yutaka Tamai; Yusuke Yamagishi; Toshizumi Miyamoto; Yuzou Sano
  Mokuzai Gakkaishi, 64, 1, 1, 9, 2018, [Peer-reviewed]
  Japanese, Scientific journal
• A pronounced improvement of the kappa number reduction and pulp properties associated with the use of extracellular enzymes secreted by selected fungal strains
  Sitompul Afrida; Toshihiro Watanabe; Yutaka Tamai
  BioResources, 12, 4, 8272, 8285, North Carolina State University, 01 Nov. 2017
  English, Scientific journal
• Optimization of simultaneous saccharification and fermentation conditions with amphipathic lignin derivatives for concentrated bioethanol production
  Ningning Cheng; Keiichi Koda; Yutaka Tamai; Yoko Yamamoto; Taichi E. Takasuka; Yasumitsu Uraki
  BIORESOURCE TECHNOLOGY, 232, 126, 132, May 2017, [Peer-reviewed]
  English, Scientific journal
• Association of amphipathic lignin derivatives with cellobiohydrolase groups improves enzymatic saccharification of lignocellulosics
  Yoko Yamamoto; Ningning Cheng; Keiichi Koda; Kiyohiko Igarashi; Yutaka Tamai; Yasumitsu Uraki
  CELLULOSE, 24, 4, 1849, 1862, Apr. 2017, [Peer-reviewed]
  English, Scientific journal
• Ectomycorrhizal fungal communities associated with Quercus dentata in a coastal broadleaf forest
  H. Arai; Y. Tamai; T. Yajima; K. Obase; T. Miyamoto
  MYCOSPHERE, 8, 4, 561, 567, 2017, [Peer-reviewed]
  English, Scientific journal
• The influence of water quality on aquatic fungal communities in headwater streams
  Yamamoto Kohei; Miyamoto Toshizumi; Nagasaka Akiko; nagasaka yu; Tamai Yutaka; Yajima Takashi
  The Japanese Forest Society Congress, 127, 394, 394, THE JAPANESE FORESTRY SOCIETY, 2016
  Japanese, [in Japanese]
• Dehydrogenative Polymerization of Coniferyl Alcohol in Artificial Polysaccharides Matrices: Effects of Xylan on the Polymerization
  Qiang Li; Keiichi Koda; Arata Yoshinaga; Keiji Takabe; Masatsugu Shimomura; Yuji Hirai; Yutaka Tamai; Yasumitsu Uraki
  JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 63, 18, 4613, 4620, May 2015, [Peer-reviewed]
  English, Scientific journal
• Ectomycorrhizal colonization and growth of the hybrid larch F-1 under elevated CO2 and O-3
  Xiaona Wang; Laiye Qu; Qiaozhi Mao; Makoto Watanabe; Yasutomo Hoshika; Akihiro Koyama; Korin Kawaguchi; Yutaka Tamai; Takayoshi Koike
  ENVIRONMENTAL POLLUTION, 197, 116, 126, Feb. 2015
  English, Scientific journal
• Effect of charcoal and fallen-leaves of black locust on water relations of black pine seedlings
  Watanabe Hanami; Fujita Saki; Meng Fakeng; Tamai Yutaka; Saito Hideyuki; shibuya Masato; Koike Takayoshi
  The Japanese Forest Society Congress, 126, 0, 255, 255, THE JAPANESE FORESTRY SOCIETY, 2015, [Peer-reviewed]
  Japanese, [in Japanese]
• Amphipathic lignin derivatives to accelerate simultaneous saccharification and fermentation of unbleached softwood pulp for bioethanol production
  Ningning Cheng; Yoko Yamamoto; Keiichi Koda; Yutaka Tamai; Yasumitsu Uraki
  BIORESOURCE TECHNOLOGY, 173, 104, 109, Dec. 2014, [Peer-reviewed]
  English, Scientific journal
• Biobleaching of Acacia kraft pulp with extracellular enzymes secreted by Irpex lacteus KB-1.1 and Lentinus tigrinus LP-7 using low-cost media
  Sitompul Afrida; Yutaka Tamai; Toshihiro Watanabe; Mitsuru Osaki
  WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY, 30, 8, 2263, 2271, Aug. 2014, [Peer-reviewed]
  English, Scientific journal
• Situation after 10 years of the colonies of Tricholoma matsutake in the Todo fir (Abies sachalinensis) forest in the northeast of Hokkaido
  Gisusi Seiki; Yoshida Shigeichi; Uenaka Hiroaki; Tamai Yutaka
  The Japanese Forest Society Congress, 124, 321, 321, THE JAPANESE FORESTRY SOCIETY, 2013
  Japanese, 村田らは、1992～2000年に北海道北東部のトドマツ林において、マツタケの発生調査を行うとともに、マツタケ発生環境の改善を目的に除間伐、腐植層除去などを行った。この際、子実体の発生位置およびB層上面に露出させたマツタケの菌糸層先端部の位置から目視でシロ先端部を決め、調査区A（20m x 50m）では29個、調査区B（25m x 40m）では13個のシロが確認された。 2011年に、10数年経過した調査地の状況を把握するため、マツタケのシロを探索した。2000年当時の資料を基に、シロの大まかな位置を推測し、近傍の表土を除去し目視でマツタケのコロニーを判断し、異なる数方向の先端部を決めた。また、温度記録計を深度10cmの土壌中に埋設し、温度変化を測定した。その結果、調査区Aでは25個、調査区Bでは9個のシロを確認した。本州アカマツ林での報告に比べ、本調査地におけるシロの成長は遅く、その一因として積算温度が少ないことが考えられた。 【引用文献】村田ら（2001）北林試研報38:1-22
• Ectomycorrhizal richness of hybrid larch F1 under elevated CO2 and O3
  Wang Xiaona; Kawaguchi Korin; Qu Laiye; Tamai Yutaka; Watanabe Makoto; Koike Takayoshi
  The Japanese Forest Society Congress, 124, 203, 203, THE JAPANESE FORESTRY SOCIETY, 2013
  Japanese, We studied the ectomycorrhiza (ECM) infection rate and species richness of a new hybrid larch F1 (Larix gmelinii var. japonica × L. kaempferi) with elevated CO2 and O3. Two-year-old planting stocks were planted in Open Top Chamber (OTC) system. We conducted four fumigation treatments: Control (ambient air), O3 (60ppb), CO2 (600ppm), CO2+O3, totally 16 chambers (volume=1.2m×1.2m×1.2m, n=4), all the seedlings were planted in OTC from July 2011 and harvested in Oct 2012(4 repetitions). The ECM infection rate and symbiotic specificity were estimated, after morphological and molecular analysis 6 types of ECM were found: Tomentella sp.,
• Symbiotic relationships between DSE fungi (Phialocephala fortinii) and Labrador-tea (Ledum palustre).
  Tamai Yutaka; Ueyama Shun; Miyamoto Toshizumi; Yajima Takashi
  The Japanese Forest Society Congress, 124, 326, 326, THE JAPANESE FORESTRY SOCIETY, 2013
  Japanese, 北海道に自生するエゾイソツツジは酸性土壌のみならず塩基性土壌にも生育している。蛇紋岩土壌中のエゾイソツツジの細根からDSEとして知られるPhialocephala fortiniiが高頻度で分離された。7種類の培地上で種子発芽試験を行い、得られた実生にP. fortiniiを接種した。グロースチャンバー内で6ヶ月間培養した後、細根内菌糸の観察、地上高、最大根長、着葉数、地際直径、乾燥重量、総葉面積を測定した。種子発芽および実生の生残率についてP. fortiniiの影響は認められなかった。接種区の細根内には、DSEの特徴である有隔壁褐色菌糸およびミクロスクレロティアが観察されたが、エリコイド菌根様のコイル状菌糸は認められなかった。接種後6ヶ月の実生では非接種区と比較して接種区で地上部の発達が見られた。各処理区の実生の測定の結果、地上高、最大根長、TR比、着葉数には処理区間で有意差は見られなかったが、地際直径、乾燥重量および総葉面積については非接種区と比較して各々有意に増加した。
• Relationship between intraspecific variations and host insects of Ophiocordyceps nutans collected in Japan
  Fumito Sasaki; Toshizumi Miyamoto; Aki Yamamoto; Yutaka Tamai; Takashi Yajima
  MYCOSCIENCE, 53, 2, 85, 91, Mar. 2012
  English, Scientific journal
• Fabrication of honeycomb-patterned cellulose material that mimics wood cell wall formation processes
  Yasumitsu Uraki; Yutaka Tamai; Takuro Hirai; Keiichi Koda; Hiroshi Yabu; Masatsugu Shimomura
  MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS, 31, 6, 1201, 1208, Aug. 2011, [Peer-reviewed]
  English, Scientific journal
• Ectomycorrhizal fungi promote growth of Shorea balangeran in degraded peat swamp forests
  Maman Turjaman; Erdy Santoso; Agung Susanto; Sampang Gaman; Suwido H. Limin; Yutaka Tamai; Mitsuru Osaki; Keitaro Tawaraya
  WETLANDS ECOLOGY AND MANAGEMENT, 19, 4, 331, 339, Aug. 2011
  English, Scientific journal
• Identification of ectomycorrhiza types with difference nitrogen load on three larch species grown under two phosphorous levels
  Wang Xiaona; Mao Qiaozhi; Qu Laiye; TAMAI Yutaka; WATANABE Makoto; KITA Kazuhito; KOIKE Takayoshi
  The Japanese Forest Society Congress, 123, Pb174, Pb174, THE JAPANESE FORESTRY SOCIETY, 2011
  English
• MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF Pisolithus IN SOIL UNDER EUCALYPTUS PLANTATIONS IN BRAZIL
  Maria Catarina Megumi Kasuya; Irene da Silva Coelho; Daniela Tiago da Silva Campos; Elza Fernandes de Araujo; Yutaka Tamai; Toshizumi Miyamoto
  REVISTA BRASILEIRA DE CIENCIA DO SOLO, 34, 6, 1891, 1898, Nov. 2010, [Peer-reviewed]
  English, Scientific journal
• Buried charcoal layer and ectomycorrhizae cooperatively promote the growth of Larix gmelinii seedlings
  K. Makoto; Y. Tamai; Y. S. Kim; T. Koike
  PLANT AND SOIL, 327, 1-2, 143, 152, Feb. 2010
  English, Scientific journal
• Screening of white rot fungi for biobleaching of Acacia oxygen-delignified kraft pulp
  Sitompul Afrida; Yutaka Tamai; Toshihiro Watanabe; Mitsuru Osaki
  WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY, 25, 4, 639, 647, Apr. 2009, [Peer-reviewed]
  English, Scientific journal
• Mycorrhizal synthesis of four ectomycorrhizal fungi in potted Populus maximowiczii seedlings
  Keisuke Obase; Yutaka Tamai; Takashi Yajima; Toshizumi Miyamoto
  MYCOSCIENCE, 50, 2, 143, 145, Mar. 2009, [Peer-reviewed]
  English, Scientific journal
• Preparation of activated carbon from peat
  Yasumitsu Uraki; Yutaka Tamai; Masato Ogawa; Sampang Gaman; Seiichi Tokurad
  BioResources, 4, 1, 205, 213, Feb. 2009
  English, Scientific journal
• Morphological and genetic characteristics of the entomopathogenic fungus Ophiocordyceps nutans and its host insects
  Fumito Sasaki; Toshizumi Miyamoto; Aki Yamamoto; Yutaka Tamai; Takashi Yajima
  MYCOLOGICAL RESEARCH, 112, 1241, 1244, Oct. 2008, [Peer-reviewed]
  English, Scientific journal
• Mycorrhizal colonization status of plant species established in an exposed area following the 2000 eruption of Mt. Usu, Hokkaido, Japan
  Keisuke Obase; Yutaka Tamai; Takashi Yajima; Toshizumi Miyamoto
  LANDSCAPE AND ECOLOGICAL ENGINEERING, 4, 1, 57, 61, May 2008, [Peer-reviewed]
  English, Scientific journal
• The molecular phylogeny and design of specific PCR primers of Cordyceps nutans
  SASAKI FUMITO; TAMAI YUTAKA; YAMAMOTO AKI; MIYAMOTO TOSHIZUMI; YAJIMA TAKASHI
  Abstracts of Papers Presented at the Meeting of the Mycological Society of Japan, 52, 103, 103, The Mycological Society of Japan, 2008
  Japanese, Cordyceps nutans Pat.はカメムシ類にのみ寄生を行なうとされている冬虫夏草菌であるが，寄生されるカメムシ類の種についての報告は少なく，カメムシ目レベル以下の寄主特異性に関しては全く明らかにされていない．本研究ではC. nutansのrDNA-ITS領域の変異と寄主の種との関連性の検討を行なった．さらに，得られた結果に基づき，C. nutans特異的PCRプライマーを設計した．北海道苫小牧および江別，山形，福島，京都，鹿児島より採取された56系統のC. nutansを供試し，各子実体の寄主となっていたカメムシの種を同定した．プライマーセットITS1fおよびITS4を用いて5.8S rDNAを含むITS領域をシーケンシングし，得られた配列についてKimura 2-parameter modelにより遺伝的距離を算出後，近隣結合法で系統樹を作成した．さらにシーケンスで得た他種の昆虫病原性糸状菌の同領域配列を参照し，C. nutansに特異的な配列部分よりプライマーの設計を行なった．56系統のC. nutansの寄主となっていたカメムシ類は4科10属15種に分類された．系統樹には遺伝的距離が0.090以上離れた二つのクレードが形成された．各クレードでC. nutansの寄主は異なり，片側のクレードに属するC. nutansはヘリカメムシ科カメムシに選択的に寄生を行ない (Type 1)，他方のクレードに属するC. nutansはその他の科のカメムシに寄生を行なっていた (Type 2)．ヘリカメムシ科カメムシは，主に草本植物の茎より吸汁を行なう草地性のカメムシであり，Type 2の寄主となる樹上で生活を行なうことの多いカメムシとはハビタットや吸汁対象がやや異なる．この結果から，ITS領域内にType 2にのみアニーリングサイトを持つフォワードプライマーと，両タイプにアニーリングサイトを持つリバースプライマーを作成し，その選択性を確認した．
• Honeycomb-like architecture produced by living bacteria, Gluconacetobacter xylinus
  Yasumitsu Uraki; Junji Nemoto; Hiroyuki Otsuka; Yutaka Tamai; Junji Sugiyama; Takao Kishimoto; Makoto Ubukata; Hiroshi Yabu; Masaru Tanaka; Masatsugu Shimomura
  CARBOHYDRATE POLYMERS, 69, 1, 1, 6, May 2007, [Peer-reviewed]
  English, Scientific journal
• Mycorrhizal associations in woody plant species at the Mt. Usu volcano, Japan.
  Obase Keisuke; Tamai Yutaka; Yajima Takashi; Miyamoto Toshizumi
  Mycorrhiza, 17, 3, 209, 215, Springer Berlin / Heidelberg, May 2007
  English, We investigated the association between ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungi and pioneer woody plant species in areas devastated by the eruption of Mt. Usu, Japan, in 2000. We observed eight woody plant species at the research site, most of which were associated with ECM and/or AM fungi. In particular, dominant woody plant species Populus maximowiczii, Salix hultenii var. angustifolia and Salix sachalinensis were consistently associated with ECM fungi and erratically associated with AM fungi. We found one to six morphotypes in the roots of each ECM host and, on average, two in the roots of each seedling, indicating low ECM fungal diversity. ECM colonization ranged from 17 to 42% of root tips. Using morphotyping and molecular analyses, 15 ECM fungi were identified. ECM fungi differed greatly between hosts. However, Laccaria amethystea, Hebeloma mesophaeum, Thelephora terrestris and other Thelephoraceae had high relative colonization, constituting the majority of the ECM colonization in the roots of each plant species. These ECM fungi may be important for the establishment of pioneer woody plant species and further revegetation at Mt. Usu volcano.
• The effect of pioneer ectomycorrhizal fungi from Volcano Usu on performance of Populus maximowiczii seedlings.
  obase keisuke; tamai yutaka; yajima takashi; miyamoto toshizumi
  The Japanese Forest Society Congress, 118, 94, 94, THE JAPANESE FORESTRY SOCIETY, 2007
  Japanese
• Regeneration and ectomycorrhiza formation of Larix kaempferi at Mt. Komagatake, Hokkaido.
  Usami Horoka; Tamai Yutaka; Yajima Takashi; Miyamoto Toshizumi
  The Japanese Forest Society Congress, 118, 93, 93, THE JAPANESE FORESTRY SOCIETY, 2007
  Japanese
• Effects of slope aspect and position on soil microbial community and litter decomposition
  yamamoto mayumi; miyamoto toshizumi; tamai yutaka; yazima takashi
  The Japanese Forest Society Congress, 118, 686, 686, THE JAPANESE FORESTRY SOCIETY, 2007
  Japanese
• Changes in viability of the seeds of some tree species infected with Racodium therryanum
  Kondou Wataru; Miyamoto Toshizumi; Sano Yuzou; Tamai Yutaka; Yajima Takashi
  The Japanese Forest Society Congress, 118, 638, 638, THE JAPANESE FORESTRY SOCIETY, 2007
  Japanese
• Pileus differentiation and pileus-specific protein expression in Flammulina velutipes
  Yuichi Sakamoto; Akira Ando; Yutaka Tamai; Takashi Yajima
  FUNGAL GENETICS AND BIOLOGY, 44, 1, 14, 24, Jan. 2007, [Peer-reviewed]
  English, Scientific journal
• Arbuscular mycorrhizal fungi increased early growth of two nontimber forest product species Dyera polyphylla and Aquilaria filaria under greenhouse conditions
  Maman Turjaman; Yutaka Tamai; Erdy Santoso; Mitsuru Osaki; Keitaro Tawaraya
  MYCORRHIZA, 16, 7, 459, 464, Oct. 2006
  English, Scientific journal
• Patterned cellulose films
  Yasumitsu Uraki; Chiaki Matsumoto; Yutaka Tamai; Takao Kishimoto; Makoto Ubukata; Hiroshi Yabu; Masaru Tanaka; Masatsugu Shimomura
  Research Progress in Pulping and Papermaking, 2006, 898, 903, 2006, [Peer-reviewed]
  English, International conference proceedings
• Inocybe nitidiuscula, new to Japan
  Keisuke Obase; Takahito Kobayashi; Toshizumi Miyamoto; Yutaka Tamai; Takashi Yajima
  Mycoscience, 47, 5, 293, 297, Springer Japan, 2006, [Peer-reviewed]
  English, Scientific journal
• Inoculation with the ectomycorrhizal fungi Pisolithus arhizus and Scleroderma sp. improves early growth of Shorea pinanga nursery seedlings
  Maman Turjaman; Yutaka Tamai; Hendrik Segah; Suwido Hester Limin; Young Cha Joo; Mitsuru Osaki; Keitaro Tawaraya
  New Forests, 30, 1, 67, 73, Jul. 2005, [Peer-reviewed]
  English, Scientific journal
• Optimum temperature and pH for mycelial growth of Cordyceps nutans Pat. (Ascomycetes)
  Fumito Sasaki; Toshizumi Miyamoto; Yutaka Tamai; Takashi Yajima
  International Journal of Medicinal Mushrooms, 7, 1-2, 301, 304, 2005, [Peer-reviewed]
  English, Scientific journal
• Allocation of C-14-carbon in two species of larch seedlings infected with ectomycorrhizal fungi
  LY Qu; T Shinano; AM Quoreshi; Y Tamai; M Osaki; T Koike
  TREE PHYSIOLOGY, 24, 12, 1369, 1376, Dec. 2004
  English, Scientific journal
• Isolation of vegetable wasps and plant worms, Cordyceps nutans, from fruit-body tissue.
  Fumito Sasaki; Toshizumi Miyamoto; Yutaka Tamai; Takashi Yajima
  Journal of invertebrate pathology, 85, 2, 70, 3, Feb. 2004, [International Magazine]
  English, Scientific journal, We isolated Cordyceps nutans from the stipe and abdominal tissues of fruit bodies using a surface sterilization method. Hyphal growth was observed in inocula from both the stipe and abdominal tissue. Some strains from discharged ascospores were obtained and colony characteristics were compared to the strains isolated from the tissues. Colonies of isolates from ascospores grew quite slowly. Isolates of 43 from the 52 examined fruit bodies formed colonies similar to those from ascospores. To confirm the success of isolation, we analyzed by PCR-RFLP of the ITS regions of rDNA samples from fruit bodies, isolates from fruit bodies, and isolates from ascospores. All the isolates obtained from stipe and abdominal tissues presented identical patterns. In this study, we report the first successful isolation of C. nutans from fruit-body tissue using a surface sterilization method.
• Influence of light on the morphological changes that take place during the development of the Flammulina velutipes fruit body
  Yuichi Sakamoto; Yutaka Tamai; Takashi Yajima
  Mycoscience, 45, 5, 333, 339, Springer Japan, 2004, [Peer-reviewed]
  English, Scientific journal
• Protein expressions during fruit body induction of Flammulina velutipes under reduced temperature
  Y Sakamoto; A Ando; Y Tamai; K Miura; T Yajima
  MYCOLOGICAL RESEARCH, 106, 222, 227, Feb. 2002, [Peer-reviewed]
  English, Scientific journal
• A gene encoding a hydrophobin, fvh1, is specifically expressed after the induction of fruiting in the edible mushroom Flammulina velutipes
  A Ando; A Harada; K Miura; Y Tamai
  CURRENT GENETICS, 39, 3, 190, 197, May 2001, [Peer-reviewed]
  English, Scientific journal
• Effect of environmental temperature on a small-scale biodegradation system for organic solid waste
  S Horisawa; Y Sakuma; Y Tamai; S Doi; M Terazawa
  JOURNAL OF WOOD SCIENCE, 47, 2, 154, 158, 2001, [Peer-reviewed]
  English, Scientific journal
• Isolation and characterization of a novel anionic peroxidase cDNa found in poplar (Populus nigra) suspension cultured cells
  Yoshiaki Kato; Yoh Sakuma; Tomonori Azuma; Akira Ando; Kiyoshi Miura; Keiji Takabe; Yutaka Tamai
  Journal of Wood Science, 47, 3, 165, 170, 2001, [Peer-reviewed]
  English, Scientific journal
• Seasonal change in tangential strain on the inner bark in white birch(Betula platyphylla var. Japonica)
  YOSHIDA Masato; TAMAI Yutaka; SANO Yuzou; TERAZAWA Minoru; OKUYAMA Takashi
  Nagoya University forest science, 19, 21, 28, 名古屋大学農学部附属演習林, Dec. 2000
  English, 農林水産研究情報センターで作成したPDFファイルを使用している。
• Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood. (VI). Relationship between wood and pulp properties brought by their within-tree variations on E. camaldulensis.:Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood (VI)
  Ona Toshihiro; Sonoda Tetsuya; Ito Kazuya; Shibata Masaru; Tamai Yutaka; Kojima Yasuo
  Journal of the Japanese Technical Association of the Pulp and Paper Industry, 49, 9, 1347, 1356, JAPAN TECHNICAL ASSOCIATION OF THE PULP AND PAPER INDUSTRY, 1995
  Japanese, The relationship between wood and kraft pulp properties was examined using within-tree tree variation on two trees of E. camaldulensis grown in Western Australia. Many pulp properties were related to wood properties analysed by chemical determination of wood components and their structures, at 1% level of significance. Multiple regression analysis of pulp properties on wood properties revealed significant independent variables as follows :
  1. Pulp yield : total-extractives content, arabinose and galactose mol.%.
  2. Sheet density : total-extractives content, galactose mol.%, cellulose content/hemicellulose content.
  3. Burst factor : xylose mol.%, total-extractives content.
  4. Breaking length : xylose mol.%, lignin S/G ratio.
  5. Tear factor : basic density, hemicellulose content.
  6. Folding endurance : total-extractives content.
  7. Unbleached brightness : total-extractives content, galactose and arabinose mol.%, hemicellulose content.
  8. Kapper number : total-extractives content, arabinose mol.%, cellulose content/hemicellulose content.
  Significant regression equations at 1% level were obtained for all pulp properties except tear factor (5% level). And we also look forward to applying them for prediction of whole-tree pulp properties by an increment core from the representative height without cutting a tree.
• Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood. (VII). Relationship between wood and pulp properties brought by their within-tree variations on E. globulus.:Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood (VII)
  Ona Toshihiro; Sonoda Tetsuya; Ito Kazuya; Shibata Masaru; Tamai Yutaka; Kojima Yasuo
  Journal of the Japanese Technical Association of the Pulp and Paper Industry, 49, 10, 1567, 1576, JAPAN TECHNICAL ASSOCIATION OF THE PULP AND PAPER INDUSTRY, 1995
  Japanese, The relationship between wood and kraft pulp properties was examined using within-tree variation on two trees of Eucalyptus globulus grown in Western Australia. Many pulp properties were related to wood properties analysed by chemical determination of wood components and their structures, at 1% level of significance. Multiple regression analysis of pulp properties on wood properties revealed significant independent variables as follows :
  1. Pulp yield : lignin content, holocellulose content.
  2. Sheet density : extractives content, hemicellulose content, lignin S (syringyl) /G (guaiacyl) ratio, mannose mol.%.
  3. Burst factor : lignin S/G ratio, cellulose content/hemicellulose content, extractives content, holocellulose content.
  4. Breaking length : lignin S/G ratio, cellulose content/hemicellulose content.
  5. Tear factor : basic density.
  6. Folding endurance : extractives content.
  7. Unbleached brightness : extractives content.
  8. Kapper number : extractives content, arabinose mol.%, basic density.
  Significant regression equations at 1% level were obtained for all pulp properties except folding endurance (5% level) and tear factor (10% level). And we also look forward to applying them for prediction of whole-tree pulp properties by an increment core from the representative height without cutting a tree.
• Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood (VIII). The most appropriate height for sampling an increment core for E. camaldulensis and E. globulus.:Studies on Decision of Selection Indexes for Quality Breeding of Eucalypt Pulpwood (VIII)
  Ona Toshihiro; Sonoda Tetsuya; Ito Kazuya; Shibata Masaru; Tamai Yutaka; Kojima Yasuo
  Journal of the Japanese Technical Association of the Pulp and Paper Industry, 49, 11, 1713, 1726, JAPAN TECHNICAL ASSOCIATION OF THE PULP AND PAPER INDUSTRY, 1995
  Japanese, Pulp properties were predicted by regression equations using weighted averages of wood properties at given heights under 3.3 m, which were suitable to take an increment core, and using whole-tree wood properties. And the most appropriate height was examined for the core sampling in order to do quality breeding of Eucalyptus camaldulensis and E. globulus as pulpwood.
  As pulp properties, pulp yield, sheet density, burst factor, breaking length, tear factor, folding endurance, unbleached brightness and kapper number were nominated. And as wood properties, basic density, chemical determination of wood components, lignin syringyl/guaiacyl ratio and neutral sugar mol % constituting hemicellulose were utilyzed.
  The most appropriate heights were 2.32.8 m above ground for E. camaldulensis, and 2.8 m for E. globulus against pulp properties, and 2.8 m for both species against pulpwood productivity because predicted values at those heights were almost all within predicted whole-tree values ± 3 %.
  Consequently, the most suitable heights to take an increment core were decided as 2.8 m above ground for both species. And the whole-tree pulp properties and pulpwood productivity were able to be estimated using one increment core with chemical analysis only.
• ELECTROFUSION OF THE AUXOTROPHIC MUTANTS OF RHIZOCTONIA-SOLANI
  T YOKONO; Y TAMAI; K MIURA; T KAYAMA; M HYAKUMACHI
  MOKUZAI GAKKAISHI, 34, 2, 176, 180, 1988
  English, Scientific journal

• Mycorrhization and growth of larch container seedlings
  Yamamoto Takahiro; Tamai Yutaka; Miyamoto Toshizumi; Kita Kazuhito; Ishizuka Wataru, The Japanese Forest Society Congress, 130, 444, 27 May 2019
  [in Japanese], THE JAPANESE FORESTRY SOCIETY, Japanese
• 土場を想定した踏圧が植栽苗木の成長に及ぼす影響調査(予報) : グイマツ雑種F₁を対象にした試験地の設定—Effects of soil compaction by forestry machines on growth of planted seedlings (preliminary experiment) : Establishment of study site with hybrid larch F₁
  菅井 徹人; 横山 聡子; 市川 一; 藤戸 永志; 藤田 早紀; 玉井 裕; 渡部 敏裕; 佐藤 冬樹; 小池 孝良, 北方森林保全技術 = Technical report for boreal forest conservation of the Hokkaido University Forests / 北海道大学北方生物圏フィールド科学センター森林圏ステーション 編, 36, 20, 24, Feb. 2019
  札幌 : 北海道大学北方生物圏フィールド科学センター森林圏ステーション, Japanese
• カラマツコンテナ苗の成長に及ぼす水分環境の影響
  西井あす香; 菅井徹人; 玉井裕; 斎藤秀之; 澁谷正人; 小池孝良, 北方森林研究, 66, 27‐30, 28 Feb. 2018
  Japanese
• Biodiversity of ectomycorrhiza of 3 larch species grown under different phosphorous and nitrogen levels in weathered volcanic ash soil
  WANG Xiaona; MAO Qiaozhi; QU Laiye; TAMAI Yutaka; WATANABE Makoto; Koyama Akihiro; KOIKE Takayoshi, Boreal forest research, 61, 45, 47, 18 Feb. 2013
  The Boreal Forest Society, English
• The Study on Mycorrhizal Status of Current-Year Acer mono Seedlings
  Yoshida Marina; Tamai Yutaka; Miyamoto Toshizumi; Yajima Takashi, Eurasian Journal of Forest Research, 14, 1, 39, 41, Aug. 2011
  We investigated mycorrhizal status of current-year Acer mono seedlings at different regenerated sites. The arbuscular mycorrhizae (AM) formation degree, spore density, available phosphorus (AP) and total nitrogen (TN) contents of samples were tested. Our results indicated that current-year A. mono seedlings may not be obligatory mycorrhizal species since AM colonization was not found in some of the seedlings in the bare sites. The spore density in the soils can play an important role in AM formation since it has significantly positive correlations with the frequency of vesicles and hyphae. AP and TN contents in the soil also have close relationships with the frequency of hyphae in roots., Hokkaido University Forests, EFRC, English
• Vegetation and Colonization Status of Mycorrhizal and Endophytic Fungi in Plant Species on Acidic Barren at Crater Basin of Volcano Esan in Hokkaido, Japan
  Fukuchi Souta; Obase Keisuke; Tamai Yutaka; Yajima Takashi; Miyamoto Toshizumi, Eurasian Journal of Forest Research, 14, 1, 1, 11, Aug. 2011
  We investigated the colonization status of mycorrhizal and endophytic fungi in roots of plants established on an acidic barren at volcano Esan, Hokkaido, Japan. In total, 87 individuals of 21 plant taxa were investigated in four different vegetation sites and the surrounding area. Ericaceous plants such as Empetrum nigrum var. japonicum, Ledum palustre var. diversipilosum, Vaccinium vitis-idaea var. minus and Loiseleuria procumbens were the main colonizers at the study sites and dominated under even the most severe conditions of low soil moisture and nutrient content. They were associated with ericoid mycorrhizal (ERM) fungi at all vegetation sites and erratically with dark septate endophytic (DSE) fungi. They commonly associated together with arbuscular mycorrhizal (AM) fungi only at sites where Sasa senanensis dominated. Among the ericaceous plants, only Enkianthus campanulatus associated with AM and DSE fungi and had no associations with ERM fungi. Other herbaceous and woody plants associated commonly with AM or erratically with DSE fungi, except for Carex sp. and Polygonum spp. which erratically associated with AM and DSE fungi. Mycorrhizal associations were common in representative vegetation on the crater basin of Mt. Esan. In particular, ERM associations might play a significant role in invasion and establishment of ericaceous plants, and also in the development of plant communities in the harsh environment at Mt. Esan., Hokkaido University Forests, EFRC, English
• Shortening Effect of Charcoal on the Cultivation Period of Bunashimeji Mushroom (Hypsizygus marmoreus)
  SUGIYAMA Ryoji; TAMAI Yutaka; YAJIMA Takashi; MIYAMOTO Toshizumi; HARADA Akira, Journal of the Japan Wood Researh Society, 57, 4, 223, 226, 25 Jul. 2011
  日本木材学会, Japanese
• 桧山地方における海岸生イタヤカエデ林の林分構造と更新
  武田 展也; 夏目 俊二; 宮本 敏澄; 玉井 裕; 矢島 崇, 北海道大学演習林研究報告 = Research bulletin of the Hokkaido University Forests, 67, 1, 25, 33, Oct. 2010
  北海道桧山地方上ノ国町に成立する海岸生イタヤカエデ林の分布と林分構造及び更新動態を検討した。イタヤカエデは海岸段丘、海食崖に小面積の純林状林分を形成し、研究対象地における海岸林面積の48.8％を占めていた。調査した3林分の上層高は、8.3～10.8mで、胸高断面積合計は23.42～30.31m2/haであった。全ての林分でイタヤカエデが胸高断面積率99%以上を占め、中～下層の発達しない一斉林型を呈した。全上木に占める萌芽由来幹の割合は64.5～84.6%と高かった。林床には大型草本やササ類が密生し稚樹は少なかった。樹齢階別頻度分布における単幹の分布は一山型に近く、萌芽由来幹のピークとほぼ一致したが、萌芽由来幹は単幹に比べ広い樹齢階に分布していた。更新は不連続で、機会的に生じた実生更新とほぼ同時に生じかつ持続的な萌芽更新によって林分が維持されてきたと考えられた。, 北海道大学北方生物圏フィールド科学センター森林圏ステーション, Japanese
• 蛇紋岩土壌に植栽したグイマツ雑種F1の成長と外生菌根形成に対する窒素付加の影響
  笠小春; 渡辺誠; 玉井裕; 小池孝良; 柴田英昭; 高木健太郎; 野村睦, 日本森林学会大会学術講演集(CD−ROM), 120th, ROMBUNNO.PA3-06, 25 Mar. 2009
  Japanese
• Combinational effects of various distributions of charcoal and ectomycorrhiza in soil on the growth of Larix gmelinii. seedlings
  KOBAYASHI Makoto; KIM Yong-Suk; KOJIMA Yasuo; TAMAI Yutaka; KOIKE Takayoshi, Transactions of the Meeting in Hokkaido Branch of the Japanese Forest Society, 57, 57, 59, 21 Feb. 2009
  The Boreal Forest Society, Japanese
• Morphological and molecular characterization of Pisolithus occurring in Hokkaido Island, Northern Japan
  KASUYA Maria Catarina Megumi; COELHO Irene da Silva; TAMAI Yutaka; MIYAMOTO Toshizumi; YAJIMA Takashi, Mycoscience, 49, 5, 334, 338, 25 Oct. 2008
  Mycological Society of Japan, English
• Revegetation process on an exposed area formed by volcanic deposition at volcano Usu
  obase keisuke; yajima takashi; tamai yutaka, The Japanese Forest Society Congress, 119, 0, 538, 538, 26 Mar. 2008
  日本森林学会, Japanese
• Utilization of Kumaizasa (Sasa senanensis) for the cultivation of edible mushrooms
  谷口 啓介; 玉井 裕; 宮本 敏澄, Bamboo journal, 25, 32, 35, Mar. 2008
  竹文化振興協会, Japanese
• Note on Cordyceps brongniartii Shimazu collected from the wild in Japan
  SASAKI Fumito; MIYAMOTO Toshizumi; TAMAI Yutaka; YAJIMA Takashi, Mycoscience, 48, 5, 312, 315, 25 Oct. 2007
  Mycological Society of Japan, English
• 有珠山噴火跡地におけるヤナギ類稚樹の外生菌根菌相
  小長谷啓介; 玉井裕; 矢島崇; 宮本敏澄, 日本森林学会大会学術講演集(CD-ROM), 117th, 0, F29, 162, 03 Apr. 2006
  日本森林学会, Japanese
• 有珠山噴出物堆積地で確認された外生菌根菌
  小長谷啓介; 玉井裕; 矢島崇; 宮本敏澄; YOGANATH Adikari, 日本森林学会大会講演要旨集(CD-ROM), 116th, 0, 2B21, 216, 20 Mar. 2005
  日本森林学会, Japanese
• 噴火3年後の有珠山で確認された実生と菌根の形成状態
  小長谷啓介; YOGANATH A; 宮本敏澄; 玉井裕; 矢島崇, 日本林学会大会学術講演集, 115th, 653, 20 Mar. 2004
  Japanese
• Differential protein expression in the fruiting dikaryon and the non-fruiting monokaryon of Flammulina velutipes
  Y Sakamoto; A Ando; Y Tamai; K Miura; T Yajima, MYCOLOGICAL RESEARCH, 105, 2, 177, 182, Feb. 2001
  English
• Characterization of proteins expressed abundantly in the fruit-body of Flammulina velutipes
  Yuichi Sakamoto; Tomonori Azuma; Akira Ando; Yutaka Tamai; Kiyoshi Miura, Mycoscience, 41, 3, 279, 282, 15 Jun. 2000
  Mycological Society of Japan, English
• Characterization of proteins expressed abundantly in the fruit-body of Flammulina velutipes
  Yuichi Sakamoto; Tomonori Azuma; Akira Ando; Yutaka Tamai; Kiyoshi Miura, Mycoscience, 41, 3, 279, 282, 15 Jun. 2000
  Mycological Society of Japan, English
• Rapid prediction of native wood pulp properties by Fourier transform Raman spectroscopy
  T Ona; T Sonoda; K Ito; M Shibata; T Kato; Y Ootake; Y Tamai; Y Kojima, JOURNAL OF PULP AND PAPER SCIENCE, 26, 2, 43, 47, Feb. 2000
  English
• Chemotaxonomic Survey of Phenolics in the Leaves of 15 Birch Species
  SHEN Yanbo; JIAN Hongzhuo; NIE Shaoquan; ZU Yuangang; TAKATA Katsuhiko; TAMAI Yutaka; TERASAWA Minoru, Research bulletins of the College Experiment Forests, Hokkaido University, 57, 1, 53, 65, 2000, [Peer-reviewed]
  Hokkaido University, Japanese
• Effect of moisture content of a wood matrix on a small-scale biodegradation system for organic solid waste
  S Horisawa; Y Tamai; Y Sakuma; S Doi; M Terazawa, JOURNAL OF WOOD SCIENCE, 46, 4, 317, 321, 2000
  English
• Biodegradation of non-lignocellulosic substances (]G0003[) : Effects of hot-and cold-water extractives of sawdust on bacterial multiplication(共著)
  SUNAGAWA Masahide; HORIZAWA Sakae; TAMAI Yutaka; MATSUOKA Yuki; MIURA Tohru; TERAZAWA Minoru, Research Bulletin of the Hokkaido University Forests, 57, 1, 66, 70, 2000
  Hokkaido University, Japanese
• Screening of heterozygous DNA markers in shiitake (Lentinula edodes) using de-dikaryotization via preparation of protoplasts and isolation of four meiotic monokaryons from one basidium
  K Miyazaki; H Maeda; M Sunagawa; Y Tamai; S Shiraishi, JOURNAL OF WOOD SCIENCE, 46, 5, 395, 400, 2000
  English
• Analysis of the electrophoretic karyotype of Flammulina velutipes
  D Kim; Y Tamai; T Azuma; A Harada; A Ando; Y Sakuma; K Miura, JOURNAL OF WOOD SCIENCE, 46, 6, 466, 469, 2000
  English
• Karyotype analysis of interspecific fusants of basidiomycetes by pulsed-field gel electrophoresis
  T Yokono; Y Tamai; T Azuma; Y Sakuma; K Miura; Y Kojima; M Sunagawa; M Ohmasa, JOURNAL OF WOOD SCIENCE, 46, 6, 480, 484, 2000
  English
• Chemical Constituents of ┣DB Inonotus obliquus (/)-┫DB (]G0001[)(共著)
  SHIN Yusoo; TAMAI Y; TERAZAWA M, Eurasian Journal of Forest Research, 1, 43, 50, 2000
  Article, Hokkaido University
• Investigation of change in tangential strain on the inner bark of the stem and root of Betula platyphylla var. japonica and Acer mono during sap season
  YOSHIDA Masato; YAMAMOTO Osamu; TAMAI Yutaka; SANO Yuzou; TERAZAWA Minoru; OKUYAMA Takashi, Journal of Wood Science, 45, 5, 361, 367, 25 Oct. 1999
  Springer, English
• ナラタク属菌によるシイタクほだ木の侵害(共著)
  日本応用きのこ学会誌, 7, 2, 71, 74, 1999
• Biodegradation of nonlignocellulosic substances II: physical and chemical properties of sawdust before and after use as artificial soil
  S Horisawa; M Sunagawa; Y Tamai; Y Matsuoka; T Miura; M Terazawa, JOURNAL OF WOOD SCIENCE, 45, 6, 492, 497, 1999
  English
• Biodegradation of nonlignocellulosic substances I: system for complete decomposition of garbage using sawdust and aerobic soil bacteria
  M Terazawa; S Horisawa; Y Tamai; K Yamashita, JOURNAL OF WOOD SCIENCE, 45, 4, 354, 358, 1999
  English
• Cloning and Sequence Analysis cDNA for the Gene FVFD 30,Speci tically Expressed During Fruiting Body Development in ┣DBElammulina(/)-┫DB ┣DBvelutipes(/)-┫DB(共著)
  KIM Doolyi; AZUMA Tomonori; HARADA Akira; SAKUMA Yoh; ANDO Akira; TAMAI Yutaka; MIURA Kiyoshi, Mushroom Technology and Biotechnology, 7, 3, 95, 99, 1999
  A Flammulina velutipes CDNA library was constructed using mRNA from 7-day-old culture after fruiting induction, and a cDNA clone for the FVFD30 gene was selected by differential screening. The FVFD30 transcript was detected from 1 to 10day-old culture which forms primordia and particularly expressed at higher level in 7-day-old culture, but not in cultures before fruiting induction, several days after primordium formation and after that. It is suggested that the FVFD30 is involved in the initial stages of fruiting body development in F. velutipes. The FVFD30 cDNA contains an open reading frame encoding a putative protein of 319 amino acid residues (MW=34,592), which might belong to the oxidoreductase family., Japanese Society of Mushroom Science and Biotechnology, English
• Histological Characteristics and Decay Ability to Wood of Betula platyphylla SUKATCHEV var. japonica (MIQ.) HARA and Abies sachalinensis (FR. SCHM.) MAST. of 5 Hokkaido Armillaria in Japan
  Cha Joo Young; Tamai Yutaka; Miyamoto Toshizumi; Igarashi Tsuneo, Research bulletins of the College Experiment Forests, Hokkaido University, 53, 2, 235, 244, Sep. 1996
  Hokkaido University, Japanese
• Analyses of fusants in edible mushrooms
  SUNAGAWA Masahide; TAMAI Yutaka; NEDA Hitoshi; MIYAZAKI Kazuhiro; MIURA Kiyoshi, Journal of the Japan Wood Researh Society, 41, 10, 945, 948, 25 Oct. 1995
  日本木材学会, English
• Development of Flammulina velutipes (Curt.: F_R.) SING, on street trees
  CHA Joo Young; MIYAMOTO Toshizumi; TAMAI Yutaka; IGARASHI Tsuneo, Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society, 43, 42, 44, 28 Feb. 1995
  The Boreal Forest Society, Japanese
• APPLICATION OF RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) MARKERS .1. ANALYSES OF FUSANTS IN EDIBLE MUSHROOMS
  M SUNAGAWA; Y TAMAI; H NEDA; K MIYAZAKI; K MIURA, MOKUZAI GAKKAISHI, 41, 10, 945, 948, 1995
  English, Introduction scientific journal
• SEPARATION OF LARGE DNA-MOLECULES FROM PLEUROTUS-CORNUCOPIAE BY PULSED-FIELD GEL-ELECTROPHORESIS
  Y TAMAI; T YOKONO; M SUNAGAWA; Y KOJIMA; K MIURA, MOKUZAI GAKKAISHI, 41, 10, 952, 955, 1995
  English, Introduction scientific journal
• Wood rotting ability of 5 biological species of Armillaria mellea complex in Hokkaido
  CHA Joo Young; TAMAI Yutaka; IGARASHI Tsuneo, Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society, 42, 146, 148, 28 Feb. 1994
  The Boreal Forest Society, Japanese
• Electrical Fusion of Edible Basidiomycetes Interspecific Fusant between Pleurotus Species
  玉井 裕, 北海道大學農學部 演習林研究報告, 48, 2, 445, 461, Sep. 1991
  北海道大学農学部演習林, Japanese
• CHARACTERIZATIONS OF THE STRAINS OF BASIDIOMYCETES WITH BAVENDAMM REACTION
  Y TAMAI; K MIURA, MOKUZAI GAKKAISHI, 37, 7, 656, 660, 1991
  English
• ELECTRICAL FUSION OF PROTOPLASTS BETWEEN 2 PLEUROTUS SPECIES
  Y TAMAI; K MIURA; T KAYAMA, MOKUZAI GAKKAISHI, 36, 6, 487, 490, 1990
  Japanese

• 森林資源科学特論, 2024年, 修士課程, 農学院
• 森林資源科学特論演習, 2024年, 修士課程, 農学院
• 林産学特論Ⅰ, 2024年, 修士課程, 農学院
• 林産学特論演習Ⅰ, 2024年, 修士課程, 農学院
• 林産学実習, 2024年, 学士課程, 農学部
• 一般教育演習(ﾌﾚｯｼｭﾏﾝｾﾐﾅｰ), 2024年, 学士課程, 全学教育
• パルプ・製紙学, 2024年, 学士課程, 農学部
• 木質バイオマス変換化学, 2024年, 学士課程, 農学部
• 木質バイオマス変換学, 2024年, 学士課程, 農学部
• 林産製造学実験, 2024年, 学士課程, 農学部
• 森林科学総合実習Ⅰ, 2024年, 学士課程, 農学部
• きのこ学, 2024年, 学士課程, 農学部
• 学外実習Ⅰ, 2024年, 学士課程, 農学部
• 学外実習Ⅰ, 2024年, 学士課程, 農学部
• 森林資源生物学演習, 2024年, 学士課程, 農学部
• 学外実習Ⅰ, 2024年, 学士課程, 農学部
• 学外実習Ⅱ, 2024年, 学士課程, 農学部
• 卒業論文, 2024年, 学士課程, 農学部
• 森林科学演習Ⅰ, 2024年, 学士課程, 農学部
• 森林科学演習Ⅱ, 2024年, 学士課程, 農学部

• 日本木材学会
• 日本菌学会
• 日本きのこ学会
• リグニン学会
• 木質炭化学会
• 日本森林学会

• Research Bulletin of the Hokkaido University Forests,57(1)66-70(2000) Biodegradation of non-ligrocellulosic substances (]G0003[) : Effects of hot- and cold- water extractives of sawdust on bacterial multiplication(共著)
  2000

• Mechanism of antagonism of phyllosphere fungi against pathogen of ash dieback and their ecology
  Grants-in-Aid for Scientific Research
  01 Apr. 2023 - 31 Mar. 2026
  山岡 裕一; 玉井 裕; 岡根 泉; 石賀 康博
  1．拮抗性葉圏菌類の拮抗作用メカニズムの解明：Hymenoschyphus fraxineus子嚢胞子の発芽抑制効果がin vitroで確認されているAureobasidium pullulans（菌株No. 5029）については、生葉上でも本菌の子嚢胞子の発芽を抑制すること、細胞懸濁液接種から4週後でも生葉表面に生存することが確認できた。しかし、本年度実施した接種試験ではH. fraxineus子嚢胞子の接種による病徴の再現ができなかった。原因を調べた結果、本菌の宿主への侵入や菌糸伸長は、黄化が始まった古い葉では起こるが、緑色の若い葉では殆ど起こらないことが分かった。また、セイヨウトネリコの若い葉のメタノール抽出物には、H. fraxineus子嚢胞子の発芽を抑制する成分が含まれることが示唆された。
  2．拮抗性葉圏菌類の生態の解明：北海道で無発病のセイヨウトネリコ実生の根系から次世代シーケンサーを用いて網羅的な菌類の検出を試みた。rDNAのITS1領域を用いて解析した結果、これまでにH. fraxineusに対する拮抗性が確認されている葉圏菌類は検出されなかったが、拮抗性を有する可能性がある菌類が新たに検出された。
  H. fraxineusの子実体形成時期以前に本菌のDNAがヤチダモの枝や冬芽から検出され、本菌が枝茎内で無病徴で生存できることが分かった。このことから、枝茎内での拮抗性微生物の調査の必要性が出てきた。
  3．拮抗性葉圏菌類のトネリコ類やその他の植物に対する影響評価：A. pullulansの細胞懸濁液、またはColletotrichum fioriniae（菌株No. 7148）およびTalaromyces marneffei（菌株No. 8193）の分生子懸濁液をセイヨウトネリコ若木に接種したが、これまでのところ顕著な病徴は見られていない。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), University of Tsukuba, 23K26940
• Clarification of propagation reaction for lignin formation by using artificial polysaccharide matrix
  Grants-in-Aid for Scientific Research
  05 Apr. 2021 - 31 Mar. 2026
  浦木 康光; 堤 祐司; 玉井 裕; 綿岡 勲; 鈴木 栞; 重冨 顕吾
  当該年度は、3つの課題について検討を行い、以下の成果を得た。
  1. rCWPO-Cの高純度化と多量発現：組換体大腸菌によるタンパク質の発現と精製工程にいて、TAPS化とリフォールディングの間に遠心分離を2回の行う操作を加えた。この結果、精製rCWPO-Cの収率を維持したまま、ペルオキシダーゼの精製度を示すRZ値が約1.5倍に増加し、比活性も約1.5倍の560μmol/min/mgまで向上した。
  2.細胞壁構成多糖類間および多糖類-ペルオキシダーゼ間のの相互作用解析：木材のヘミセルロース（キシラン、グルコマンナン、キシログルカン）とセルロースとの相互作用を、平衡吸着実験と速度論的解析が可能なQCM-Dを用いて行った。両測定とも、キシログルカンがセルロースに最も吸着することが明らかとなった。また、Horseradish peroxidase(HRP)と多糖類との相互作用解析では、HRPはセルロースに対し、高い親和性を示すことも分かった。さらに、多糖類が脱水素重合体(DHP)の形成に及ぼす影響も調べ、キシログルカンがDHPを多量生成させ、加えて、5-5’縮合結合の形成も促進することが示された。この結果より、一次細胞壁が縮合構造に富む理由が解明できた。
  3.高分子リグニンの蛍光共鳴エネルギー移動（FRET)の測定：FRET測定の最初の取り組みとして、固体試料を対象とした蛍光顕微鏡でFRETが示されているリグニンと蛍光試薬ローダミンとの相互作用を、溶液中で検出することから検討した。使用したリグニンは広葉樹のクラフトリグニンである。この測定の結果、プロピレングリコールを溶媒とする溶液中で、FRETを観測することができた。モノリグノールとクラフトリグニンとのFRETの検出を試みたが、どちらも蛍光強度が弱かったために、明確なFRET検出には至っていない。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 21H04730
• A study on mechanisms of barrier function in various types of outer bark of trees
  Grants-in-Aid for Scientific Research
  01 Apr. 2020 - 31 Mar. 2023
  佐野 雄三; 玉井 裕; 重冨 顕吾
  樹皮組織の抗菌活性評価実験系の前処理（滅菌）条件の検証を行うとともに、同実験系により対象樹種を拡げて樹皮組織に対する菌類の抗菌活性評価を行った。また、前年度の研究で顕著な抗菌活性が認められたナナカマドについて、化学的なメカニズムの検討と内生菌相の解析を行った。主な成果は以下の通りである。
  【抗菌活性評価実験系の前処理（滅菌）条件の検討】前年度にサンプルの前処理として15 kGyのγ線照射が有効であることを確認したが、フレッシュな樹皮組織で必要且つ十分な線量については未検討であった。そこで、16樹種のサンプルについて3 kGy刻みで検証し、15 kGyの照射線量は妥当なレベルであることを確証した。【樹皮片に対する菌類の忌避性・成長阻害活性評価】上述の評価実験系により、新たに10樹種について試験を行った。前年度に見出されたナナカマドのような強い活性を示すものは認められなかったが、新たに2樹種（エゾマツ、オオヤマザクラ）が明らかな成長阻害活性を示した。このうちエゾマツでは、樹皮組織片とカワラタケの分断実験の結果から、その原因物質は揮発性ではないことが示唆された。【ナナカマド樹皮の抗菌活性発揮メカニズム】アミグダリンに着目し、解析を行なった。樹皮組織にも含まれること、アミグダリン（標品）がβ-グルコシダーゼとの共存下でシアン化水素を発生し、ナナカマドの樹皮組織片と同様にカワラタケの成長を阻害すること、ナナカマドから採取した樹皮組織が実際にシアン化水素を発することが確認され、アミグダリンがバリア機能発揮に大きく寄与していることが示唆された。【ナナカマド樹皮組織の菌叢】内生菌がバリア機能強化に寄与する可能性を検討するため、菌叢解析を行なった。内樹皮では菌が検出されず、外来の共生菌類のバリア機能発揮への寄与は小さいことが示唆された。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 20H03018
• Mechanisms to avoid occurrence of Ash dieback on the introduced ash species surviving in Japan
  Grants-in-Aid for Scientific Research
  01 Apr. 2019 - 31 Mar. 2022
  Yamaoka Yuichi
  To clarify why some introduced ash species planted in Hokkaido, including on the campus of Hokkaido University, grow well without suffering serious diseases such as Ash dieback, monitoring of the behavior of Hymenoscyphus fraxineus in the leaves of ash trees, comparison of resistance by inoculation experiments using seedlings, detection and isolation of phyllosphere fungi from the leaves of the ash trees, and screening of phyllosphere fungi against H. fraxineus were conducted. As a result, European ash (F. excelsior) trees planted on the campus of Hokkaido University were infected with H. fraxineus similar to other ash species, but they showed the ability to inhibit growth of H. fraxineus in the infected cells and tissues. Some phyllosphere fungi, Diaporthe pseudomangiferae and Aureobasidium pullulans were antagonistic to H. fraxineus, indicating they may contribute to the inhibition of H. fraxineus in European ash.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), University of Tsukuba, 19H02988
• Investigation of lignin formed in the mimetics of wood cell wall and clarification of lignification-related compounds
  Grants-in-Aid for Scientific Research
  01 Apr. 2018 - 31 Mar. 2021
  Uraki Yasumitsu
  This study clearly demonstrated the effect of hemicelluloses on ligninfication through lignin formation in the artificial polysaccharide matrices; xylan contributed to lignin formation and generation of 8-O-4' interunitary linkage, which was a major linkage in native lignin, while glucomannan inhibited lignin formation. In addition, xyloglucan, which located only at primary wall of tree, was found to enhance the frequency of 5-5' interunitary linkage.
  From the analysis of solution structure for isolated lignins by using size-exclusion chromatograph equipped with multi-angle laser light scattering detector, 5-5' linkage was found to be closely related to the densed structure, especially much compact structure of lignin fraction with larger molar mass compared to that with small molar mass.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 18H03954
• Ecology and diversity of Hymenoscyphus fraxineus, the causal agent of ash dieback in Europe in the areas near origin, and risk assessment as invasive plant pathogen
  Grants-in-Aid for Scientific Research
  01 Apr. 2015 - 31 Mar. 2018
  YAMAOKA Yuichi; MASUYA Hayato; ABE Junichi; TAMAI Yutaka; YAMAGUCHI Takehiro
  Hymenoscyphus fraxineus causeing a lethal disease known as ‘ash dieback’ of Fraxinus excelsior in Europe is considered to be originated from East Asia. In Japan, this fungus produces apothecia on decomposing leaves of manshurian ash, F. mandshurica from middle July to early September. Results of detection of the fungus from periodically collected leaves of F. mandshurica by real-time PCR assays using species specific primers revealed that after infected the living leaves of by ascospores, H. fraxineus endophytically inhabited in them until defoliation. This fungus was also able to infect other Fraxinus species, including F. excelsior, F. pennsylvanica, and F. augustifolia, but no serious damages like ash dieback were observed in these ashes except for one population of F. pennsylvanica in Hokkaido. Some resistant reactions controlling movement of the fungus into stem tissues and/or environmental factor like overwinter condition might affect on symptom development.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), University of Tsukuba, 15H04506
• Lignification in polysaccharide matrix mimicking wood cell wall and clarification of lignin structure -control factor
  Grants-in-Aid for Scientific Research
  27 Jun. 2014 - 31 Mar. 2018
  Uraki Yasumitsu
  An aim of this study is to elucidate lignin formation mechanism (lignification), especially influence of hemicelloses, with polysaccharide matrix mimicking wood cell wall structure. Polysaccharide matrix was successfully prepared by the deposition of hemicelluloses, xylan and glucomannan, onto bacterial cellulose. Dehydrogenative polymerization of coniferyl alcohol, which was one of monolignols, was attempted in the presence of such polysaccharide matrix. As a result, the polymerization was accelerated by xylan deposition, but was inhibited by glucomannan.
  In addition, the structure of the resultant polymerized product (Dehydronation Polymer: DHP) was investigated on a size-exclusion chromatography equipped with a laser light-scattering detector by the comparison with solution structure of a non-branched lignin model compound that is comprised of only 8-O-4’ linkage. This investigation revealed that DHP had a significant frequency of branched structure.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 26252022
• Combination Effect of elevated O3 and CO2 on growth of larch species and species diversity of ectomycorrhizae
  Grants-in-Aid for Scientific Research
  01 Apr. 2014 - 31 Mar. 2016
  KOIKE Takayoshi; TAMAI Yutaka; WATANABE Makoto
  We studied colonization of ectomycorrhiza (ECM) fungi and the species abundance of a hybrid larch F1 (Larix gmelinii var. japonica × L. kaempferi) with elevated CO2 and ozone (O3). Two-year-old seedlings were planted in an Open-Top-Chamber (OTC) system with 4 gas fumigations: Control (< 6 nmol/mol), O3 (60 nmol/mol), CO2 (600 μmol/mol), and CO2+O3. After 2 growing seasons, ECM colonization and root biomass were positively affected by elevated CO2. Ozone impaired ECM colonization rate and species richness, and reduced stem biomass. However there was no clear inhibition on photosynthetic capacity by O3. Concentration of most elements (Al, Fe, Mo, P) in needles was reduced by O3 but some increased in roots (K, Mg), which may lead to distinct alteration of ECM abundance. We found no effects of combined fumigation on all parameters except P concentration in needles. Tolerance to O3 shown in hybrid larch F1 might be potentially related to ECM symbiosis changes.
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Hokkaido University, 26660119
• Clarification of hemicellulose functions using artificial wood cell wall and development of its functional materials
  Grants-in-Aid for Scientific Research
  2009 - 2011
  URAKI Yasumitsu; TAMAI Yutaka; KODA Keiichi; HIRAI Takuro; SUGIYAMA Junji
  In this study, hemicellulose-adsorbed honeycomb-patterned cellulose films termed as artificail wood cell wall were developed to investigate the function of hemicelluloses in wood cell wall and to develop the cell culture for liver cells. Tensile strength and its modulus of the cellulosic films were enhanced by the adsorption of hemicelluloses, xylan and arabinogalactan (AG). Xylan adsorption and its tensile modulus were improved by microwave irradiation. We judged proposed theory for the elucidation of deformation mechanism of wood cross-scetion upon the mechanical stress from the tensile properties of honeycomb-patterned films. As a result, the theory of bending-stretching model was suitable for the elucidation, and xylan-adsorbed film showed more fitting to the theory.
  In addition, we evaluated AG-adsorbed honeycomb-patterned film as a culture substrate for mouse liver cells. The films with small pores were found to be a new type candidate substrate for the culture. On the other hand, the films with larger pores would be suggested to be a plate for cell array, but the number of attached cell was so small. For the industrial application, this problem should be overcome.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 21380104
• Complete understanding of the nitrogen missing link in boreal forest ecosystems and evaluation of nitrogen provision and loss
  Grants-in-Aid for Scientific Research
  2008 - 2011
  HASHIDOKO Yasuyuki; HARAGUCHI Akira; KOIKE Takayoshi; HATANO Ryusuke; TAMAI Yutaka; HORIUCHI Junichi; MIYAMOTO Toshizumi
  Nitrogen imbalance of the boreal forest ecosystem has long been a mystery, called missing link of nitrogen in boreal forest. We challenged to this mystery, to practically understand the effects of climate change on forest biomass productivity in several types of boreal forests. Precise investigation of optimal culture conditions including compositions of the medium were obviously close to the reported conditions of the forest bed soil in summer seasons. The 16S rRNA gene-targeting DGGE analysis combined with gellan gum medium revealed the presence of Dugnella (class y-Proteobacteria) and Clostridiumin (phylum Firmicutes) in the A-horizon of the subarctic tundra soil, and also showed the aboveground vegetation affect on bacterial activity in soil. Thus, it was strongly suggested that scale of the elemental circulation in the boreal forests near the forest limit highly regulates acetylene reducing activity of free-living nitrogen-fixing bacteria. Also it was speculated that the low acetylene reduction in the forest bed soil would be highly regulated as corroborative events together with ericoid mycorrhizal and/or ectomycorrhizal fungi, leading to effective nitrogen supply to the forest ecosystem.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 20255002
• Investigation for functionalities of rhizo-biocomplex to minimize highly adverse conditions in association with organic sink in the rhizosphere and its utilization in agricultural use
  Grants-in-Aid for Scientific Research
  2008 - 2011
  HASHIDOKO Yasuyuki; HARAGUCHI Akira; KIMURA Atsuo; SAKIHAMA Yasuko; TAMAI Yutaka; MATSUURA Hideyuki
  We investigated rhizo-biosystems that enable to mitigate adverse soils in Kalimantan, Indonesia. Burkholderia sp. strain A-KA that had been isolated from the rhizosphere of Imperata cylindrica grown in medium-strongly acidic peatland showed a growth-helper activity toward other rhizosphere bacteria, such as Sphingomonas sp. Burkholderia mimosarum isolated from rhizosphere of paddy rice tolerant to acid-sulfate soil suppressed tropolone production of B. plantarii, a bacterium causative of rice blight disease, while promoted growth of diverse root-and seed-epiphytic bacteria. Among rhizobacteria that had isolated from dipterocarpous sapling adapting to polyphenol-rich tropical peat soil, pyrogallol-containing plant polyphenols activated Burkholderia unamae CK-43B to degrade indole and some other N-heterocyclic aromatic compounds. In the coralloid root symbiotic systems between Cycas revoluta root and a nitrogen-fixing cyanobacterium Nostoc punchiforme, a diacylglycerol was found to be the principle of hormogoniu-inducing factor on the cyanobacterium necessary to its host-recognition. Also, we successfully isolated and characterized signal compounds from a rhizobacterium Pseudomonas jessenii strain EC-S101 isolated from spinach root and from a rhizosphere fungus Trichoderma virens strain PS1-7 isolated from paddy root. In the rhizosphere, nitrous oxide emitting bacteria in tropical peat soil were missing their nitrous oxide reductase (N2OR) genes, and affected its denitrification by several secondary metabolites of plants
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 20248033
• Optimization of tropical peatland management based on carbon flow control
  Grants-in-Aid for Scientific Research
  2007 - 2010
  INOUE Takashi; HIRANO Takashi; HATANO Ryusuke; TANI Hiroshi; SAITOU Hideyuki; TAMAI Yutaka; OSAKI Mitsuru; HATA Hiroshi; HASHIDOKO Yasuyuki; URAKI Yasumitsu; TAWARAYA Keitaro; HARAGUCHI Akira; ABE Ryuichiro
  Tropical peat land is a huge carbon sink involving an ecosystem that is very fragile but rich in biodiversity. This study deployed on establishment of measures for optimum land use and land management based on the viewpoint of control of carbon flow in tropical peatland. Prevention of peat fire, restoration of devastated land, sustainable bioproduction, and the reduction of environment load are the special interest that is rendered for the approach.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 19255016
• Creation of cellulosic materials mimicking secondary wall structure in tree cell wall
  Grants-in-Aid for Scientific Research
  2006 - 2008
  URAKI Yasumitsu; HIRAI Takuro; TAMAI Yutaka; KISHIMOTO Takao; SUGIYAMA Junji
  樹木細胞壁の二次壁の特徴は、他の壁組織に比べ多量に存在するリグニンとその化学構造である。本研究では、二次壁模倣材料の創出を目的に、二次壁リグニン模倣高分子を創製して、その物性を明らかにした。さらに、ハニカムパターン化セルロースにリグニンを吸着させて二次壁模倣セルロース材料を創製して、その物性解析からリグニンが高湿度における細胞壁の強度低下を抑制することを見出すと共に、木材成分のみで高強度材料を創出できることを明らかにした。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 18380100
• Investigation of functional rhizo-biocomplex on highly adverse soil-adapting plants and application of the functional rhizo-biocomplex to agro-technology.
  Grants-in-Aid for Scientific Research
  2004 - 2007
  HASHIDOKO Yasuyuki; TAMAI Yutaka; HARAGUCHI Akira; MATSUURA Hideyuki; IWAHASHI Hitoshi; TAWARAYA Keitarou
  Using local peat soil from Central Kalimantan, Indonesia, a saprophytic soil fungus Penicillium sp. Isolate Y-1 from X. complanata seedbed was tested its seed-germination promotion activity. The seeds germinated well by means of inoculation with Y-1 fungus, but the resulting seedlings were all died after one month-incubation in the local peat soil bed. Only when the supernatant of the local soil suspension without sterilization was further inoculated to the seedbeds, the germinated seedlings that had been inoculated with Y-1 resulted in survival and normal growth of the seedlings over 6 month. This suggested that saprophytic fungi stimulate seed germination, while some soil bacteria provide nutrients to the germinated seedlings. On the other hand, in Siberian Taiga forest bed soil, oligotrophic Burkholderia and Pseudomonas occupied soil microflora, and they showed a relatively high acetylene reduction activity at 10-15℃,under a lower concentration of carbon source (0.02-0.05%). Including medium pH, these soil bacteria were highly adapted to culture conditions agreeable to the permafrost soil, so that physicochemical conditions similar to activated permafrost soil in summer seasons resulted in relatively higher nitrogen-fixing activity. Moreover, gellan gum as gel matrix allowed the bacteria to show maximal nitrogen-fixing potential. Under a field condition of newly accumulated volcanic ash soil accumulated extreme soil land in Mt. Usu, Hokkaido, the land allowed pioneer plants to possess mycorrhizal symbionts and grew dominantly. Particularly, those of willow tree saplings constitutively possessed ectomycorrhizal fungi, while herbivorous weeds, except horsetail and rasp, allowed symbiosis with arbuscular mycorrhizal fungi. Thus, it was found that pioneer plants distributing throughout fresh volcanic ash soil in Mt. Usu were dependent on mycorrhizal infection.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 16208032
• 国際共同研究シベリアカラマツ産地試験実施に向けた企画調査
  科学研究費助成事業
  2005 - 2005
  高田 克彦; 船田 良; 栗延 晋; 長坂 壽俊; 吉丸 博志; 玉井 裕
  本研究は、シベリアカラマツに関する国際共同研究実施に向けた国内外の研究者9名(研究協力者2名を含む)による企画研究である。
  研究代表者の高田は研究協力者であるOwe Martinsson(SLU, Sweden)を通じてフランス、アイスランド、ノルウェー、フィンランド、ロシア、中国、カナダ、アメリカ等のカラマツ属植物研究者との間にネットワークを構築した。その結果はシベリアカラマツに関するホームページ「SIBLARCH : http://www.siblarch.net/」の開設に結びついた。
  研究代表者の高田及び研究分担者の船田(東京農工大)及び長坂(森林総合研究所)は平成17年9月並びに11月に研究協力者であるOwe Martinsson(SLU, Sweden)を訪問してスウェーデンに設定されているシベリアカラマツ産地試験林の見学を行った。また、日本におけるシベリア産地試験林設置に伴う経費、シベリアカラマツ産地試験林を利用した国際共同研究に関する具体的な内容に討議した。これらの討議内容をもとに他の研究分担者と平成18年度以降の国際共同研究に関する協議を行った。
  研究代表者の高田はこれらの活動・協議の結果をもとに、平成17年11月に国際共同研究「産地試験林を利用したシベリアカラマツの炭素固定能力の評価」について科学研究費基盤研究(B)海外学術調査に申請するに至った。この申請研究は本企画研究のメンバーである船田(東京農工大学)と研究協力者であるOwe Martinsson(SLU, Sweden)を含む研究組織による国際共同研究である。
  日本学術振興会, 基盤研究(C), 秋田県立大学, 17638004
• Creation of artificial cell wall by mimicking the process of natural cell wall formation
  Grants-in-Aid for Scientific Research
  2003 - 2005
  URAKI Yasumitsu; TAKABE Keiji; FUKUSHIMA Kazuhiko; KONDO Tetsuo; FUNADA Ryo; TAMAI Yutaka
  An aim of this research is to clarify the construction mechanism of tree cell wall that had the hierarchical structure from molecular level to tissue level. In addition, our objective is to create an artificial cell wall by mimicking the formation process of natural wood cell wall on the basis of the results of former subjects. In this research project, we obtained experimental results and conclusions for five subjects.
  Conclusion 1.Xylan is a key hemicellulose for lignification.
  Conclusion 2.This finding for ConClusion 1 was supported by physicochemical analysis of the interaction between hemicelluloses and lignification-related compounds. These analyses were carried out on an apparatus based on the surface plasmon resonance.
  Conclusion 3.We clarified solution behavior of LCC in water, such as interaction of solvent, self-assembly of LCC molecules and formation of hydrophobic domain in the self-aggregates. We proposed LCC functions in the wood from these results.
  Conclusion 4.we developed a new analysis method, Time of Flight・Secondary Ion Mass spectroscopy (ToF-SIMS), for lignin structure, and artificial lignin polymer, which was merely comprised of β-O-4, as a lignin model for NMR assignment.
  Conclusion 4 We elucidate the cell wall formation at the cell level in relation to cell-supported proteins, microtubles and actin in addition to tissue formation.
  Conclusion 5.we developed a methodology to create artificial cell wall on the basis of findings obtained in this study.
  The artificial cell wall backbone was fabricated by the conversion of bacterial cellulose to honeycomb-patterned material. The conversion was carried out by the control of the movement of cellulose-producing bacteria.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 15208016
• 国際研究集会『Larix 2004』に向けた企画調査 ニホンカラマツを対象にした研究成果の再評価と新たな研究課題の提示
  科学研究費助成事業
  2003 - 2003
  高田 克彦; 玉井 裕; 栗延 晋; 長坂 壽俊; SZMIDT Alfred; 安江 恒
  本研究の目的は2004年9月に日本で開催される国際研究集会『Larix2004』について研究内容面からの企画準備を行うことである。具体的には、上記研究集会にむけて専門分野の異なる研究者が現在までに国内外で行われてきたニホンカラマツを対象にした研究の学術的意義を再評価し、そこでの問題点の抽出と新たな研究課題を提示することである。以下、研究実績を時系列に示す。
  平成15年5月、交付内定通知を受けて、研究費の配分を行うとともに、研究代表者及び研究分担者間で主に電子メールによって関連研究領域間での調整を行い、境界領域の研究課題提示に向けた話し合いを行った。
  平成15年6月、京都において第1回課題検討会議を行った。会議においてそれぞれの研究分担者が担当する研究分野を以下のように決定した。全体総括:高田、次代検定林分野:栗延、産地試験分野:長坂、木材強度分野:小泉、木材組織構造及び利用分野:安江、分子生物学分野:Szmidt、森林生態学分野:木佐貫、特用林産物分野:玉井。
  6月の課題検討会議以降、各研究分担者はそれぞれの研究分野において過去実施された研究・調査に関する文献収集を行う。
  平成15年12月、秋田県立大学・木材高度加工研究所において第2回課題検討会議を行った。会議において研究分野の境界領域の取り扱い、最終報告所(英文)の書式、最終報告所の配布方法等について討議を行った。
  平成16年3月、研究分担者より各研究分野において行われた過去の研究・調査に関する取りまとめが研究代表者のもとに送付され、研究代表者によってコンパイルされた。
  現在、今年9月に行われる国際研究集会において参加者への配布資料として再編集中である。
  日本学術振興会, 基盤研究(C), 秋田県立大学, 15638005
• Study on the vegetation-enbironment interaction in the rooting zone of disturbed area.
  Grants-in-Aid for Scientific Research
  2000 - 2003
  YAJIMA Takashi; MIYAMOTO Toshizumi; KIKUCHI Shun-ichi; TAMAI Yutaka
  This study was carried out to elucidate the vegetation-environment interaction in the rooting zone of plants growing on heavily disturbed area for the purpose of applying the relationships to revegetation works. To explain the vegetation-environment interaction, we selected the disturbed areas such as Mt.Usu for volcanic disturbed site which erupted in 2000, river side of Satsunai-gawa for riparian disturbed area, and mountain slopes of Hidaka district for large scale erosion disturbance area. The survey were conducted in each site for the disturbance resume, revegetation process, growth analysis of invaded trees, mycorrhiza infection to the plant roots and physical and chemical site conditions.
  On the volcanic disturbed site around the new craters of Mt.Usu, early stage of vegetation recovery process was recorded and ectomycorrhiza (ECM) or arbuscular mycorrihza (AM) types which infected to the plant roots were investigated. On the disturbed area of river sides, we investigated the stand dynamics and growth characteristics of Chosenia arbutifolia in addition to the nutrient condition of riparian zone. Further, the infection ratio, the types of ECM and seasonal dynamics of ECM infection on the roots of Salix sachalinensis seedlings were surveyed.
  And also, we investigated the culture medium of tree seedlings which expected to use for vegetation works. We succeeded in artificial infection of ECM in semi-open condition. These are the certain progress for the application to the advanced works of the vegetation-enbironment interaction systems in the rooting zone.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 12460062
• Radial growth and cell wall structure of trees grown under elevated carbon dioxide concentrations
  Grants-in-Aid for Scientific Research
  1999 - 2001
  FUNADA Ryo; TAMAI Yutaka; SANO Yuzou; KOIKE Takayoshi; MARUYAMA Yutaka
  We estimated long-term effects of elevated carbon dioxide concentrations [CO_2] on physiological and anatomical characteristics of trees, namely the stem growth, wood structure and characteristics of photosynthesis. Seedlings of larch (Larix sibirica and Larix kaempferi) and white birch (Betula platyphylla var. japonica) trees were grown in growth chambers under two [CO_2], ambient (360 ppm) and elevated (720 ppm), and with high or low levels of nutrients for one-three growing seasons. Elevated [CO_2] had no significant effects on stem height and stem diameter. However, the stem height and stem diameter were enhanced by the high level of nutrients and these increases were stimulated by elevated [CO_2]. Annual ring widths, cell numbers and cell diameters tended to increase, whereas cell wall thickness tended to decrease slightly in response to elevated [CO_2] , By contrast, there were no statistically significant differences in the relative area of cell wall, which was closely related to specific gravity of wood, indicating that elevated [CO_2] had few effects of changes in wood quality. In conclusion, there is no obvious enhancement in the capacity of carbon fixation by elevated [CO_2]. However, changes in the temporal pattern of stem growth and in anatomical features of the stem would occur under elevated [CO_2]. Although net assimilation rate under which seedlings grew was higher in elevated [CO_2] than in ambient [CO_2], little enhancement of photosynthesis rate of whole crown under elevated [CO_2] was observed because of the smaller specific leaf area and the acclimation of photosynthetic characteristics of leaves to [CO_2] which seedling grew. Such acclimation of photosynthesis was closely related to the decrease in amounts of soluble proteins and Rubisco, which is a key enzyme of photosynthesis, in leaves.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 11460076
• 有毒キノコ種の分子マーカーによる識別
  科学研究費助成事業
  1999 - 2000
  玉井 裕
  1.菌株の収集
  北海道内において中毒例の報告されている種、またはその近縁種を採取し、形態観察による種の同定、標本作製および菌株分離を行った。採取したキノコの系統数は以下の通りである。
  ベニタケ属(6種15系統)、チチタケ属(5種18系統)、テングタケ属(3種15系統)、カヤタケ属(3種11系統)、クリタケ属(3種15系統)、スギタケ属(3種9系統)、アセタケ属(2種5系統)、イッポンシメジ属(3種12系統)、イグチ属(2種6系統)、カラカサタケ属(2種4系統)、ヌメリイグチ属(4種12系統)、モエギタケ属(2種5系統)、フウセンタケ属(4種8系統)、サマツモドキ属(2種7系統)、フクロタケ属(3種6系統)、ウラベニガサ属(3種8系統)、以上50種156系統。
  2.分子マーカーの検索
  上記において採取したキノコ種を、属内において有毒種と可食(または無毒)種とを識別することを目的として、PCR用テンプレートDNAの抽出条件および、PCR法によるリボソームRNA遺伝子のIGS領域の増幅条件を検討した。テンプレートDNAは、生子実体、アルコール浸漬標本および凍結乾燥標本のいずれからもTEバッファー中で100℃、10分間の煮沸抽出処理により調製可能であることが明らかとなった。得られたテンプレートを用いてIGS領域の増幅を行い、500〜700ベースの増幅物を得たが、非特異的なバンドの出現が幾つかの系統に認められた。IGS領域長には特に明確な種特異性は認められなかった。更に、IGS領域PCR増幅物に対して、DdeI、AluI等の制限酵素を用いてRFLPパターンを取得し、種間比較を行ったが、供試菌株群については単独酵素処理による有毒種の識別は困難であった。属毎に供試菌株を増やして、生物学的種との対応も考慮しつつ、更に検討してゆく必要性があると考えられた。
  日本学術振興会, 奨励研究(A), 北海道大学, 11760119
• 担子菌遺伝子の発現メカニズムの解明
  科学研究費助成事業
  1998 - 1999
  三浦 清; 玉井 裕
  1) 子実体形成に関わる遺伝子の単離
  エノキタケ(Flammulina velutipcs)について子実体誘導処理後7日目の菌糸体からcDNAライブラリーを作成し、誘導処理前の菌糸体との間でディファレンシャルスクリーニングを行った結果、誘導処理後7日目の菌糸体で特異的に発現している多くの遺伝子のcDNAクローンを得た。これらの遺伝子のノーザン解析、cDNAシーケンス、ゲノムシーケンスを行い、遺伝子の解析を行った。またコードしているアミノ酸についてホモロジー検索を行ったところ、ハイドロフォビン様タンパク質および酸化還元酵素様タンパク質との類似性が確認されたが、他の遺伝子はホモロジーを有するものが確認できなかった。
  2) 遺伝子導入系の開発
  担子菌であるエノキタケの形質転換系を確立するために、構造的に強く発現しているGPD(グリセロールアルデヒド-3-リン酸デヒドロゲナーゼ)遺伝子のプロモーター領域とターミネーター領域を用いる実験系の構築を検討した。
  スエヒロタケ(SchizophyHum commune)において既に報告されている塩基配列を参考にしてPCRプローブを作成し、このプローブを用いてエノキタケのゲノムライブラリーより、GPD遺伝子を含むゲノムクローンを単離した。その制限酵素地図を作成し、GPD遺伝子を含む部分をサブクローニングし、これを導入系ベクターに挿入し、レポーター遺伝子としてルシフェラーゼ遺伝子をを用いてそのプロモーター活性を測定した。
  日本学術振興会, 基盤研究(C), 北海道大学, 10660155
• Exudation Mechanism of Tree Sap
  Grants-in-Aid for Scientific Research
  1998 - 1999
  TERAZAWA Minoru; SHIBUYA Masao; FUNADA Ryo; TAKAHASHI Kunihide; SANO Yuzou; TAMAI Yukata
  Sap exudation : The period of the starting point of the sap exudation of birch trees coinsides with that the earth temperatures become above 0℃. The amount of the sap exudated in the one season corelates with the atomospheric temperatures and the change in the amount of sap exudated within a day corelates with the changes in atomospheric temperatures. Production in the leaves in a summer influences the amount of sap exudation in the following spring.
  Water distribution : The sap in the tracheids disappears gradually towards winter and disappear completely in the period just before the sap exudation starts by the repetition of freezing of the xylem and its re-freezing. The recovery of the cavitation seems to be derived by the pressures in the roots. Actually, the swelling of the roots during the sap exudation process was observed. The process of the refilling of the sap in the tracheids of the xylem was photographically recorded by Cryo-SEM techniques. The osmotic pressures in the sap of xylem tracheids and the function of the water pumping proteins in roots and trunks are the next targets to be investigated.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), HOKKAIDO UNIVERSITY, 10306010
• 高度攪乱立地における微生物フロラの動態解明と緑化への応用
  1999
  Competitive research funding
• The Tree Growth and Water Relation of Boreal Forest
  Grants-in-Aid for Scientific Research
  1996 - 1997
  TERAZAWA Minoru; TAMAI Yutaka; SANO Yuzo; FUNADA Ryou; SAKAI Kenji; OHTANI Jyun
  The Tree Growth and Water Relation in Boreal Forest
  The tree growth and water relation in boreal forests were investigated. Strain gages were glued in the tangential direction of the surface of the inner bark of several trees. Diurnal change in the tangential strain were measured throughout the seasons.
  1) In winter in the boreal forests, the water in the tranks of trees frozen into ice. The diurnal change of the strain during this period coinsided with the shrinkage and swelling of the ice following the change of air temperature under zero degrees centigrate. The movement was the largest in a yaer.
  2) In early spring, shirakamba birch exudated sap through a hole drilled on the trank. Sap exudation continued for one month and stopped just on time when flowers and leaves opened. The diurnal change of the strain was the lowest in the year. Trees seemed to keep a positive pressure throughout this period for sending the sap up to the buds of flowers and leaves for their growth and opening.
  3) In spring and summer after the leaf opening, tree growed. The diurnal change of the strain in this period varied inversely with the change observed in the winter season. Namely, the trank started to shrink when air temperature started to rise after sun rise and shrinked continuously till noon and released the shrinkage when air temperature started to fall down toward evening. During night the shrinkage was revovered and swelled a little more than the starting point of the day before. The change seemed to coinside with the balance of the activities between transpiration of the leaves and water absorption from the roots. The changes were higher in sunny days because of higher transpiration and photosynthesis activities and were lower in rainy days with their lower activities.
  4) The growth curve of the trank was drawn as an integration of the difference between the shrinkage and the release of the shrinkage and following swelling. A maximum of the growth rate was observed on the end of July and the rate decreased gradually toward defoliation.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 08456083
• 熱帯産きのこ資源の開発
  Competitive research funding
• シラカンバ樹液の溢出メカニズム
  Competitive research funding
• 担子菌の染色体解析
  Competitive research funding
• Development of mushroom resources in tropical forest
  Competitive research funding
• Mechanism of Birch Sap Exudation
  Competitive research funding
• Chromosomal Analysis of Basidiomycetes
  Competitive research funding