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Interaction among blue-stain fungi associated with larch bark beetle, Ips cembraeTwo experiments of the interaction among the blue-stain fungi associated with larch bark beetle, Ips cembrae were cariied out. The distribution of blue-stain fungi in the sapwood and inner bark from the living larch tree in which I. cembrae were artificially bored was examined. The most pathogenic blue-stain fungus, C.laricicola formed axially very large lesion in the inner bark, and also caused blue stain axially in the sapwood. The fungus tended to be isolated from the distal part of the lesion or sap stain. O.laricis less extended axially in sapwood and inner bark than C.laricicola. O.piceae and O.brunenno-ciliatum only isolated from the discolored part of inner bark or sapwood just adjacent to the gallery of bark beetles. Each blue-stain fungus associated with I. cembrae revealed showing different extension in the inner bark and the sapwood of the attacked larch. The mixture inoculation of two species of blue-stain fungi, by the combination of C.laricicola vs. O.laricis, C.laricicola vs. O.brunneo-ciliatum, and C.laricicola vs. O.piceaewas carried out. Changes of trees after the inoculation were observed. The progress of the symptom on trees inoculated with the combination of C.laricicola and O.piceae was obviously delayed, compared with that of trees inoculated with only C.laricicola. The symptom on inoculated trees with the combination of C.laricicola and O.brunneo-ciliatum was also less severe than that of single inoculation of C.laricicola.

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Ophiostomatoid fungi were isolated from bark beetles and their galleries in Larix kaempferi collected in Okunikko, Tochigi, Japan. Two Ceratocystis species and nine Ophiostoma species were isolated from four species of bark beetles. Among them, Ophiostoma laricis was frequently isolated from Ips cembrae, Dryocoetes hectographus and D. baikalicus. Ophiostoma piceae was isolated with a high frequency of occurrence from I. cembrae, Polygraphus meakanensis and D. hectographus. Ophiostoma sp. Y and sp. 54 were frequently isolated from D. hectographus and D. baikalicus, respectively. Japanese larch trees approximately 25 years old were inoculated with nine fungi. Ceratocystis laricicola and C. coerulescens produced the largest lesions on the inner bark around the inoculation point and the largest dry zone in the sapwood.

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We conducted an isolation experiment from mycangia of Platypus quercivora, emerged from Quercus mongolica var. grosseserrata. Seven fungal species, Raffaelea quercivora, Sporothrix sp. Ambrosiozyma sp., Fusarium sp., Ophiostoma cf stenoceras, Candida sp., and an unidentified species, were detected from them, and R. quercivora and an unidentified species were isolated at relatively high frequencies. The unindetified species was morphologically similar to other Raffaelea species, and its rDNA sequence data also showed the similarity with Raffaelea spp. Consequently, we could isolate two Raffaelea species from the mycangia of P. quercivora.

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Ranking order changes according to DBH size were studied using the data obtained every 3 years from 9 to 24 years old in fertilized and non-fertilized Abies sachalinensis stand. For all trees in each treatment, averaged fluctuation of the ranking order became smaller with increasing stand age. The fluctuation of fertilized stand was smaller than non-fertilized one at younger stage, but both showed similar value in 24 years. The smaller ranking fluctuation of the fertilized stand means increase of trees of fixed order, suggesting clear difference in growth appeared faster in this stand than in non-fertilized one. Within a small group of 6 nearest trees, trees with maximum and minimum size occupied the 1st and last order for longer period than other trees, indicating the largest and the smallest tree were fixed at initial stage of stand growth in comparison with other trees. These results confirmed that thinning should be practiced from early growing stages.

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In a 13-year-old Quercus serrata plantation,the biomass of stems,branches and leaves and leaf area of the stand were setimated from 10 sample trees. The biomass of stems,branches and leaves were 42.7 ton/ha,8.2 ton/ha and 3.6 ton/ha,respectively.The leaf index of this stand was 5.6 ha/ha.Each organ biomass of this stand was about 0.8 times as large as that of a 11-year-old Betula grossa plantation.

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We investigated stand structure, plant species composition and diversity in managed spruce forests in Hokkaido, northern Japan. Abundances of saplings on forest floor were significantly affected by thickness of litter layer and coverage of dwarf bamboo species, both of which were highly correlated with planting density. Also that of some component species and total plant species diversity showed correlation with intensity of nurse management. These results suggest that differences in management practices greatly affected abundance of saplings, plant species composition diversity, even in plantations with similar age in a region.

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We are investigating the development of new breeding methods with Eucalyptus trees using genetic engineering. The main technology of acquiring transgenic eucalypts was that utilization of shoot primordium formation and Agrobacterium infection to precocious branches derived from shoot apex. In this report, we applied this technology (shoot-primordium transformation system) to E. grandis that is one of the major species for pulp production in Australia. As a result of transformation, all precocious branches were transformed by Agrobacterium, and their transformation rate was 1.46 calli / individual precocious branches. To improve the transformation efficiency, we investigated the concentration of auxin in the medium for selecting transformed cells. The best medium (B5 fundamental medium containing 0.06mg/l NAA and 0.2mg/l 4-PU) repressed transformed calli browning to increase number of transformed calli. In the transformation system of E. camaldulensis, just only 4-PU in the shoot-primordium inducing medium is effective as cytokinin. On the other hand, at least two kinds of cytokinin (0.2mg/l 4-PU and 0.1 mg/l or 0.2 mg/l TDZ) are necessary in the case of E. grandis. With using this improved condition, 1.8 % of transformed calli formed shoot primordium had regeneration ability. As a result of this report, shoot-primordium transformation system is applicable to the development of transfomation system in E. grandis.

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Seedlings of Larix kaempferi Carr. and Pinus densiflora Sieb. et Zucc. were raised under atmospheric(360vppm) and elevated(720vppm) CO2, and photosynthesis, water relations, and growth were compared between CO2 treatments. Growth of P. densiflora was stimulated under elevated CO2, while that of L. kaempferi was not different between CO2 treatments. In both species, photosynthetic rate(A) for same leaf intercellular CO2 concentration(Ci) was lower in those elevated under elevated CO2, but A at saturated CO2 and dA/dCi were not significantly different between treatments. Intrinsic water use efficiency(IWUE) of L. kaempferi was higher in those raised under elevated CO2 while IWUE of P. densiflora was not different between treatments. Leaf water potential and hydraulic resistance of both species were also not different between treatments.

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In order to evaluate the representativeness of a leaf in the canopy of Pasania edulis, an ever-green broad-leaved tree, the variance in the physiological characteristics among the leaves was investigated.
There was negligible difference in the potential photosynthetic capacity among the leaves. However, when their photosynthetic rates were measured at the same time in the after noon, there was a significant difference in the rate even in the photon-saturated conditions, because of the effects of the midday depression and of the sink limit.
It is quite interesting that various environmental effects were counterbalanced throughout a day and there was only a quite small difference in the accumulated daily net photosynthesis among the leaves in the top of the canopy.
In addition, when the accumulated annual net photosynthesis was estimated for each leaf, the values were converged and nearly no differences among the leaves.

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Light on forest floors is an important factor for the survival and growth of understory plants. The floors in deciduous forest has characterized by sharp deduction in irradiance from spring to summer as the overstory canopy developed. However, the forest border and canopy gap are high light environment as compared with the understory. Thus the floors in deciduous forest has various light environment. Therefore, we expect that plants in the floors has adaptable strategy to use various light. It is known that the photosynthetic system consists of many components and their organization varies depending on growth conditions. In particular, it is well known that the organization changes with growth irradiance. In generally, the fraction of chlorophyll-protein complexes increases and the fraction of Calvin cycle enzymes and electron carriers decreases with decreased light availability. In this study, Photosynthetic characteristics and nitrogen partitioning for Daphniphylum humile, evergreen understory shrub, in the different light environment in deciduous forest were examined. Mean daily PPFD incident on leaves within the understory varied from 1.4 to 24.1 mol m^-2 day^-1 in September 2002. SLA for current and one-year old leaves in the high light condition was lower than in low light condition. The SLA had a close relationship with PPFD. These result indicate that leaves were morphologically acclimation to light environments. The rates of light-saturated photosynthesis (Pmax) in current year leaves varied throughout the understory from 3.7 to 12.2 mol m-2 s-1. The maximum rate of carboxylation (Vcmax) in current year leaves varied throughout the understory from 27.1 to 60.3 mol m-2 s-1. The maximum rate of electron transport (Jmax) in current year leaves varied throughout the understory from 61.1 to 117.6 mol m-2 s-1. These parameters were linearly related with PPFD for all data pooled. These results suggest that current year leaves has suitable nitrogen for light environment and protein compositions of photosynthetic system changes. By contrast, Pmax, Vcmax and Jmax in one-year-old leaves did not vary throughout the understory. Therefore, these parameters were not related with PPFD. The leaf life span for D. humile changes with different light environment and that of D.humile in high light environment shorter than in low light environment. Therefore, we hypothesized that one-year-old leaves in high light environment was senescent leaves and nitrogen content in leaves decreased.

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INTRODUCTION Kayu putih oil is one of non-wood forest product (NWFP) extracted from fresh leaves and twigs of kayu putih (Melaleuca leucadendron LINN white tea tree, Myrtaceae) tree through distillation process. In Java, kayu putih has been previously planted in order to rehabilitate degraded and infertile areas, and PT Perhutani, a forest enterprise, has been producing kayu putih oil since 4 decades ago. In some places, farmers surrounding the forest area participate in establishment of the plantation and cultivate crops between the trees in tangya or tumpangsari system. The plantation faces a crucial problem related to annual biomass removal from the tree due to the oil extraction. The research aims to compare plantation productivity and sustainability between different locations in Java, and to propose a basic knowledge for improving management practice of this NWFP.SITE, MATERIAL AND METHODS In Java, kayu putih plantation is managed by PT Perhutani. Main stem of the trees are cut at 1.1 m height in the 4th year after the transplanting. Coppicing and the leaf-twig harvest is repeated at one-year intervals. Kayu putih oil is extracted from collected leaves and twigs at oil factory in the plantation. In this research, 3 sites were selected; i.e. Ponorogo (site P) in East Java, Gundih (site G) in Central Java and Indramayu (site I) in West Java. The research was done within October 2000 to September 2002.In each site, plantation of various stand ages were selected and square plots of 20 m x 20 m were set. The trees are planted in 3 m x 1 m spacing (in P and I) and 2 m x 1 m (in G). D0 (diameter at the bottom of the tree) and number of tree per plot were measured and counted. In every plot, 10 sample trees were harvested following to ordinal commercial harvesting method and weighed individually. A sub-sample of leaf-twig and branch was taken for dry weight measurement in laboratory. Kayu putih oil was extracted from 5 kg of leaf-twig sub-samples per plot in a laboratory by water/steam distillation soon after harvesting. The trend of productivity in relation to stand age was estimated by using regression analysis. Plantation and oil production records collected by the enterprise were also used for the study. RESULT AND DISCUSSIONS In all sites, productivity increased with stand age to a maximum amount at about 20 to 30 years old. After that, there were indications that production would be gradually reduced. These indications showed that productions sustainability is not guaranteed in old stands. Average biomass and kayu putih oil varied among sites. Leaf-twig production in site I was estimated at 2.42 t ha-1 yr-1, followed by G at 1.97 t ha-1 yr-1 and P at 1.42 t ha-1 yr-1. Oil production in site I was also higher than other two sites. Alluvial soil and availability of stagnated water like a paddy-field may have contributed to high production in site I. The tree basically grows better in the areas of high water availability, with combinations of other favorable environmental factors.Exploitation on kayu putih plantation resulted in large amount of annual biomass removal. The tree cannot assist and protect soil fertility, as well as crop productions. Treatment is needed to maintain production sustainability for older stands (30 years and up).

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The weeping cherry trees in Kakunodate Town,which is designated as the Natural Monument of Japan, were researched to make the plan for conservation. Height, DBH (diameter in breast height), and environmental conditions are investigated for all the 147 designated trees. Mean height was 11.4 m and mean DBH was 59.0 cm with wide variety from 5.1 to 19.0 m in height and from 28 to 117 cm in DBH. Although the mean DBH was increased in about 9cm to compare with the data observed in 27 years ago, mean height decreased in about 0.9 m. The higher trees in 27 years ago showed the larger decrease in height. When the trees are on the decline, their branches on higher position are often observed to wither. The decline in tree vigor seemed to be on progress in the weeping trees in Kakunodate. One of the main reasons for the decline seemed to be the suppression by other large trees, such as fir, ginkgo, and oak trees. Heavy suppression made the vigor of weeping cherry trees declines. The cherry trees, which grow along the street, enlarge their crown toward the direction to the street, because there is no suppress trees in the street. In addition to the suppression, consolidation were also important factors to lose the vogore of cherry trees. On the basis to the present results, maintenance and recovery of the vigor of weeping cherry trees are planning. It is also important to establish the monitoring methods which the regional people in Kakunotade are able to made, because the regional people will be watching the trees day by day. This research was a part of the Emergent Research Project and Conservation Planning Project of the Weeping Cherry Trees in Kakunodate which were conducted by the Board of Education, Kakunodate Town, Akita, Japan.

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We investigated the effects of disturbance and topographic environment on tree community dynamics of a selectively cut conifer-hardwood mixed stand using logistic regression. All living trees in the study area (6.72ha) were tagged, and their diameter were measured before each logging. We measured the location of all living trees, cut stumps and fallen trees in 2002. Topographic factors had effect on dynamics of trees in broad range of size and were main factor affecting growth and mortality of large trees. Disturbance and vegetation had effects on recruitment and growth of small trees. While recruitment of conifers was positively affected by abundance of large conifers, recruitment of hardwoods was promoted by death of large conifers. This suggests that gaps created by logging of conifers are often replaced by hardwoods, and hardwoods should increase their dominance in long-term dynamics.

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