Tsuyoshi Kobayashi

Kagawa University · Faculty of Agriculture

Moso bamboo (Phyllostachys edulis; Syn: P. pubescens) shows small-scale flowering events within a stand intermittently. Synchronous large-scale flowering across the stands are rare, although such phenomena are occasionally observed for related species such as P. bambusoides and P. nigra var. henonis. In the present study, we detected an unprecedent...

We propose a microscale phloem-sap-dynamics sensor device to obtain the index of an internal plant condition regarding the transportation of primary photosynthates in phloem, which is an essential indicator of stable crop production under controlled-growth environments. In detail, we integrated a conventional Granier sensor with a thermal-flow sens...

We propose a pure photosynthates extraction sensor device integrated with highly-precise phloem/xylem position identification to quantitatively monitor the components of internal higher plants, which is a key indicator for controlling stable crop production. The essential functions of the device are high-precisely identifying phloem/xylem positions...

Semi-naturally occurring Japanese larch (Larix kaempferi) saplings originating from planted trees are often observed in riparian habitats around Nikko National Park, Japan, and they may be affecting the structure and functioning of endemic riparian vegetation. To evaluate possible larch establishment in riparian habitats, we examined the abovegroun...

Phloem is the main pathway of photosynthate transport in vascular plants and it plays an important role in the forest carbon cycle by transferring carbon from the atmosphere to the soil. Pulse labelling using stable carbon isotope is one of the best ways to study phloem transport in trees. The carbon fixed by photosynthesis in a plant can be follow...

Four ecotypes of A. thaliana (L.) (Ct-1, Pf-0, Old-1 and Per-i) from low to high latitudes were grown under different light (300 micro mol photon m-2s-1 and 150 micromol photon m-2s') and temperature (22 and 14 degreesC) conditions to investigate their effects on phenotypic plasticity and ecotypic variations in plant growth and first flowering time...

To investigate the direct physiological effects of CNU (canopy nitrogen uptake), three mist solutions (control, N1, and N2 with 0.03, 13.1, and 32.7 kg NH4+-N·ha–1, respectively) were sprayed on Japanese red pine (Pinus densiflora Sieb. et Zucc.) seedlings three times a week for three months. Waterproof sheets protected the surface soil during mist...

For 383 Poaceae species harvested over the Japanese islands and stored as herbarium specimens along several decades, we determined C3 and C4 types of photosynthesis from leaf stable carbon isotope ratio (δ13C). Then, we sought the relationships between C4 species richness and climatic factors or habitat types. Except for the two Panicum species (P....

The allelopathic potential of 102 Bangladesh rice cultivars (60 traditional and 42 high Yielding) against four test plant species, cress (Lepidium sativum L.), lettuce (Lactuca sativa L.), barnyardgrass (Echinochloa crus-galli (L.) Beauv) and Echinochloa colonum (L.) Link was determined for shoot and root growth. In the two-way analysis of variance...

In order to more accurately evaluate the functional activity of forest stands by canopy production and evapotranspiration, we improved the methods for field measurements and statistical modeling to estimate foliage configuration (spatial distribution of leaves) while simultaneously reconstructing the three-dimensional photosynthetically active phot...

We investigated how removal of understory dwarf bamboo (Sasa kurilensis Makino et Shibata) affected growth and water-use of young Betula ermanii Cham. trees in a secondary forest in northern Japan. We compared current-year shoot morphology, leaf water-relations characteristics and whole-tree water use of B. ermanii trees growing with dwarf bamboo i...

Hydroxyl radical (OH) is one of the most highly reactive of all active oxygen species. Aqueous-phase OH is photochemically generated in polluted dew droplets on needle surfaces of Japanese red pine (Pinus densiflora Sieb. et Zucc., an evergreen coniferous tree) in declining pine forests. In former studies, we examined the effects of OH-generating m...

The present study aimed to evaluate the short-term biomass accumulation of forest trees exposed to wet acidic depositions. A hierarchical Bayesian model of tree growth was developed based on the data of a short-term experiment in which 2-year-old Japanese red pine (Pinus densiflora Sieb. et Zucc.) seedlings were exposed to aqueous phase OH radicals...

Arisaema sikokianum Franch. et Sav. (Araceae) is one of the most beautiful ornamental Arisaema species. Species in this genus demonstrate a unique sexual dimorphism based on corm size. When the corm size is small the sex expression is male, and it changes to female as the corms enlarge. Because of this strict size-based sexual dimorphism, there is...

To investigate the effects of aqueous phase oxidants on the needle gas exchange of pine seedlings, simulated dew waters generating hydroxyl radicals (·OH) were sprayed onto the needle surfaces of pine seedlings. The nutrient contents and amounts of epicuticular wax of pine needles were also determined as a parameter with the effects of ·OH-generati...

Plantago asiatica L. (Plantaginaceae) is a perennial herb that is distributed over a wide range of habitats from exposed to shaded sites in lowlands to the subalpine zone in Japan. We investigated the patterns of biomass allocation and population structures based on the frequency distribution of individual plants in order to clarify the extent of p...

In the understory of Japan Sea type beech (Fagus crenata Bl.) forests, a beech seedling bank persists at the forest floor where the seedlings are shaded by dwarf bamboo (Sasa kurilensis Makino et Shibata). The culm density of dwarf bamboo is reduced by shading from the overstory. To determine the effect of the dwarf bamboo on the photosynthetic pro...

Japanese fir (Abies firma) forests on the urban-facing side ofMt. Oyama, eastern Japan are frequently exposed to acidic depositions. These forests have been declining more severely than those on the mountain-facing side. Chlorophyll, N, Mg, K, Ca, P and Al contents were determined for current, one- and two-year-old needles collected from the crown...

The hydroxyl radical (*OH) is generated in polluted dew on the needle surfaces of Japanese red pine (Pinus densiflora Sieb. et Zucc.). This free radical, which is a potent oxidant, is assumed to be a cause of ecophysiological disorders of declining trees on the urban-facing side of Mt. Gokurakuji, western Japan. Mists of *OH-generating N(III) (HNO2...

Plantago asiatica is a perennial herb that is distributed over a wide range of east Eurasia. The population structure, growth and reproduction in exposed (E-) and shaded (S-) populations of P. asiatica were examined in the Kanto District of eastern Japan. In both populations, the plant size structure showed a bimodal distribution during spring to e...

Two summer annual C4 grasses with different trampling susceptibilities were grown as potted plants, and diurnal leaf gas exchange and leaf water potential in each grass were compared. The maximum net photosynthetic rate, leaf conductance and transpiration rate were higher in the trampling-tolerant Eleusine indica (L.) Gaertn. than in trampling sens...

Regeneration of beech (Fagus crenata) forests depends on the formation of canopy gaps. However, in Japan Sea-type beech forests, a dwarf bamboo (Sasa kurilensis) conspicuously occupies sunny gaps. Therefore,F. crenata seedlings must escape the severe interference ofS. kurilensis in the gaps and persist beneath a closed canopy of the beech forest. W...

Field gas exchange and water potential in the leaves of a C3 dicot, Plantago asiatica L., and a C4 monocot, Eleusine indica Gaertn., which dominate in trampled vegetation in eastern Japan were surveyed during the growing periods for two consecutive years. Net photosynthetic rate (P N) of E. indica increased with photosynthetic photon flux density (...

The growth and reproduction of Japanese forbs (Artemisia princeps and Piantago asiatica) and grasses (Digitaria ad-scendens and Eleusine indica) treated to 25 tramplings (3 g m-2) per week were investigated in relation to the toughness (tensile strength) of organs. The perennial erect forb, A. princeps, was the most sensitive to trampling in terms...

Photosynthesis and seedling survival under contrasting light and water conditions were investigated for some C3 dicotyledons and C4 monocotyledons with different trampling susceptibilities. For the summer-annual monocotyledons, the trampling-tolerant Eleusine indica appeared to be more sun-adapted than the trampling-sensitive Digitaria adscendens [...

In a secondary forest formed by deciduous trees of Quercus serrata Thunb., three stands of understory dominated by dwarf-bamboo Pleioblastus chino were analysed as a function of the number of years after the last mowing. They were mowed in 1982(S82), 1987(S87) and just before the growing season of 1993(S93). As the time from the last mowing increas...

The structure of the aerial parts of Pleioblastus chino Makino, an evergreen dwarf bamboo, was surveyed with special reference to the C/F ratio (the ratio of non-photosynthetic organs to photosynthetic ones in dry weight). The number of years from the last management (mowing) of P. chino was different in each of these stands. The length of P. chino...

The effects of disturbance by trampling and vegetation removal on herbaceous communities and their micro-environments were examined at two sites with different levels of shade. The dominant species of the original vegetation were the perennial herb Artemisia princeps at the sunny site and the dwarf-bamboo Pleioblastus chino at the shady site. With...

主催：JST/CREST，Vrije University, ALTERRA, IBPC International workshop on H2O and CO2 exchanges in Siberia (2nd international WS on C/H2o/Energy balance and climate over boreal regions with special emphasis on eastern Siberia), 26-28 Jan., 2006, Amsterdam, p.19-22.