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1.
The fine root (diameter ≤2.0 mm) biomass and morphology of Japanese red pines (Pinus densiflora) grown under different aboveground conditions (i.e., high and low competitive environments) were examined in a pine–cypress
mixed forest. All P. densiflora subject trees were about 40 years old, and the aboveground condition (i.e., size) of red pines appeared to be influenced
by the surrounding Japanese cypress (Chamaecyparis obtusa). Smaller P. densiflora exhibited lower fine root biomasses, shorter root lengths, and lower root tip densities, but longer specific root lengths
and higher specific root tip densities relative to larger pines. These results suggest that P. densiflora may adjust the morphological traits of fine roots to the different conditions in biomass allocation to fine roots of individuals
with different aboveground growth. 相似文献
2.
To elucidate the differences in the leaf water relations of Pinus densiflora Sieb. et Zucc. growing in different soil moisture conditions, we examined the pressure-volume curve and the diurnal changes in the stomatal conductance, the transpiration rate, and the leaf water potential. The leaf water relations were compared using field-grown 40-year-old pine trees growing on the upper and lower parts of a slope. We also compared the leaf water relations of potted 4-year-old saplings growing at pF 4.2 and pF 1.8 soil moisture levels for almost 1 year. The values of the ratio of symplasmic water at turgor loss point to symplasmic water at saturated point (Vp/Vo) and bulk modulus of elasticity () of both the adult trees on the upper part of the slope and the potted saplings growing on pF 4.2 soil moisture were higher than those values of both the adult trees on the lower part of the slope and the potted saplings growing on pF 1.8 soil moisture, respectively. The field-grown adult tree and the potted saplings growing under long-term water stress tended to reduce their stomatal conductance in response to the acute soil drying. It is suggested that P. densiflora growing under long-term water stress rapidly closed its stomata in response to soil drying and avoided losing water, and could also rapidly absorb water with reducing water loss because of the decrease in the leaf pressure potential derived from the high values. 相似文献
3.
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied. 相似文献
4.
Pinus densiflora and P. thunbergii, native to Japan, are highly susceptible to pine wilt disease caused by infection with a pine wood nematode (Bursaphelenchus xylophilus). Trees of these susceptible species have occasionally been found surviving in forests that are extensively damaged by this disease. Seedlings from a part of surviving trees that were selected as resistant families indicate lower mortality rates after the infection. The factors that prevent the symptoms from developing in resistant families of a susceptible species, P. densiflora, as based on the analysis of the pathogens behavior in the tree tissue and the anatomy of the resistant families, are presented in this paper. Nematode populations remained lower in the stems of seedlings from resistant families of P. densiflora than in the stems of non-resistant families. Areas dysfunctional in water transport developed in the stems of resistant families, but did not reach a size large enough to seriously block the ascent of sap. These results suggest that there are systems within the seedlings that prevent nematode migration and reproduction. The 2-year-old seedlings from resistant families of P. densiflora, however, did not suppress the pathogen activity. Numerous branches are a visible characteristic in the seedlings of some resistant families. The arrangement of the resin canals, the only channels in the tree to the pathogen migration, was disoriented at the joints between the branches and the main stem. Such a structure may be effective as a barrier to nematode dispersal. 相似文献
5.
An allometric model that explains the mechanism of the difference in the slope of the Reineke equation (A) among species was proposed based on the allometric relationships of mean tree height (H) to quadratic mean diameter D (H ∝ D
θ
) and stand density N (H ∝ N
δ
), i.e., A = θ/δ. The proposed model was fitted to Japanese cypress (Chamaecyparis obtusa Endl.) and red pine (Pinus densiflora) stands. The allometric exponents θ and δ were, respectively, 0.8995 and −0.5000 for cypress and 0.8612 and −0.6619 for pine. The difference between cypress and pine
was significant for δ but not for θ. Inserting the exponents into the model resulted in predicted slopes of −1.7991 for cypress and −1.3011 for pine. The difference
in the slope of the Reineke equation between the two species was produced by characteristics related to the tree crown, rather
than characteristics related to stem slenderness. The proposed model enables us to estimate the slope of the Reineke equation
from commonly measured stand attributes, such as mean tree height and quadratic mean diameter. Therefore, the proposed model
is expected to be practical and convenient for estimating the slope of the Reineke equation and for explaining the mechanism
of its variation among species. The model should be also accepted as a generalized model of the stand density versus quadratic
mean diameter relationship, whereas the original Reineke equation should be seen as a specific case of this model. 相似文献
6.
Spatial pattern of recruitment is an important factor influencing population dynamics of plant communities. The spatial pattern is determined by seed dispersal and by the spatial variability of germination and initial survival. In the process of forest expansion following farmland abandonment, mid- and late-successional species are often dispersed in pioneer forests by birds. This could result in an aggregated spatial pattern of seeds that could influence the dynamics of these species in mixed pioneer forests. In the sub-Mediterranean area, mid- and late-successional species such as Quercus pubescens (downy oak) and Fagus sylvatica (European beech) are expected to replace pioneer Pinus species. Using a point sampling method we demonstrated that beech and oak seedlings (height <2 m) have a clumped distribution in the understorey of pine. This could result from an aggregated dispersal by jays (dispersal effect) or from preferential recruitment in particular habitats (habitat effect). To test these hypotheses we proposed a statistical analysis of spatial patterns of regeneration of beech and oak. Ground cover variables (i.e. cover by rock outcrops, herbs, box shrubs, mosses or pine) did not differ significantly around seedlings as compared with random sample plots. Likewise, clumped seedlings had growth similar to isolated seedlings, thus refuting the hypothesis of preferential location in the most favourable microsites. Aggregated dispersal seems to be involved in the process of regeneration. Since beech and oak seedlings have contrasting ecological demands, we discuss the implication of this pattern for the replacement dynamics of pine by these species. 相似文献
7.
Yasumasa Hirata 《Journal of Forest Research》2008,13(3):147-154
This study aims to estimate stand density and stand volume in Cryptomeria japonica and Chamaecyparis obtusa stands from high-resolution satellite data and verify the reliability and uncertainty of the data. Sixty circular sample
plots of 0.04 ha each were established. Their stand densities were estimated from the number of tree crowns derived from high-resolution
satellite data using the watershed method. Stand densities derived from field surveys in the sample plots were compared with
those obtained from high-resolution satellite data by stand age class. As a result, there was a positive correlation between
them for sample plots of 41 years of age and over (R = 0.82); however, there was no correlation between them for sample plots of 40 years and under. Individual diameters at breast
height (DBH) were estimated from crown areas obtained from high-resolution satellite data for the two species. Using the estimated
DBH, individual tree heights were predicted from the height–diameter curves. Stand volumes were estimated from the sum of
individual volumes, which were derived from volume formulas having two variables, i.e., DBH and height. Stand volumes derived
from the field survey were compared with those obtained from high-resolution satellite data. The correlation coefficient between
them for stands of 41 years of age and over was 0.78. 相似文献
8.
The allometric relationships between mean weights of components, such as stems, branches and leaves and tree weight as well
as their time-trajectories, were studied with data of self-thinning Pinus densiflora stands with different densities. The allometric relationships existed between the weights of stems, branches and leaves and
the tree weight during the course of self-thinning. The stem weight ratio increased with increasing tree weight because the
allometric coefficient in stem was higher than unity, whereas the branch weight ratio and the leaf weight ratio decreased
because the allometric coefficients in branches and leaves were less than unity. An allometric power relationship existed
between mean component weight and mean tree weight during the course of self-thinning. The time-trajectory of mean component
weight (w
o) and density (ρ) in the early growth stage was expressed as a mathematical model which incorporates the allometric power
relationship into the Tadaki’s model, whereas the model for describing w
o-ρ trajectory in the later growth stage was derived by combining the allometric power relationship with 3/2 power law. The
two models, Tadaki’s model and 3/2 power law, showed a good fit to data from P. densiflora stands. The time-trajectories of mean tree weight (w)-density (ρ) or w
o-ρ initially almost moves nearly vertically in the low-density stand, moves along a steep curve and an inclined curve in the
medium- and high-density stands, respectively, and gradually approaches self-thinning line in the early stage of stand development,
whereas they reached and moved along the self-thinning line in the later stage of stand development. The self-thinning exponents
were determined to be 1.71, 1.19 and 1.13 for the trees, 2.38, 1.33 and 1.20 for the stem, 3.16, 1.55 and 1.46 for the branches,
2.66, 1.39 and 1.35 for the leaves in the low-, medium- and high-density stands, respectively. The 3/2 power law of self-thinning
is derived on the basis of simple geometric model of space occupation by growing trees, but allometric growth of tree and
components can make the slope of the self-thinning line being different from −3/2. The reasons that the self-thinning exponents
of components in the low-density stand were greater than those in the medium- and high-density stands were discussed. 相似文献
9.
The problem of salinized soils has become one of the most serious constraints to agricultural and forest productivity. With the purpose of enhancing salt stress tolerance of Populus tomentosa, we transformed this tree species with spermidine synthase （SPDS） genes derived from an apple by an Agrobacterium-mediated method. Four transgenic clones were confu＇med by PCR and Southern blot analysis. As well, the expression of introduced SPDS genes was analyzed by real-time quantitative PCR. 相似文献
10.
Yoshitaka Kubojima Seiichi Kanetani Takeshi Fujiwara Youki Suzuki Mario Tonosaki Hiroshi Yoshimaru Hiroharu Ikegame 《Journal of Wood Science》2008,54(6):443-450
A dead tree of Pinus armandii Franch. var. amamiana (Koidz.) Hatusima (abbreviated to PAAm) was obtained from a natural habitat on Tanega-shima Island and various properties
of its wood were investigated. Grain angle was measured and soft X-ray analysis was undertaken to obtain the density in each
annual ring. Unit shrinkage and dynamic properties were measured by shrinkage, bending, and compression tests. Variations
of wood properties in the radial direction, relationships of wood properties to density, and annual ring width were examined.
Roughly speaking, variations in the radial direction of the grain angle, twist angle by drying, Young’s modulus and strength
in static bending, absorbed energy in impact bending, compressive Young’s modulus, compressive strength, and compressive proportional
limit corresponded to the variation of annual ring width. As a result, it was determined that if PAAm is afforested artificially
for the purposes of lumber production and conservation, the annual rings of logs should not be too widely spaced. Wood properties
of PAAm were similar to those of Japanese black pine (Pinus thunbergii Parl.), which is another representative pine on Tanegashima Island.
This study was presented in part at the 56th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007 相似文献
11.
This study evaluated oxalic acid accumulation and bioremediation of chromated copper arsenate (CCA)-treated wood by three brown-rot fungi Fomitopsis palustris, Coniophora puteana, and Laetiporus sulphureus. The fungi were first cultivated in a fermentation broth to accumulate oxalic acid. Bioremediation of CCA-treated wood was then carried out by leaching of heavy metals with oxalic acid over a 10-day fermentation period. Higher amounts of oxalic acid were produced by F. palustris and L. sulphureus compared with C. puteana. After 10-day fermentation, oxalic acid accumulation reached 4.2 g/l and 3.2 g/l for these fungi, respectively. Fomitopsis palustris and L. sulphureus exposed to CCA-treated sawdust for 10 days showed a decrease in arsenic of 100% and 85%, respectively; however, C. puteana remediation removed only 18% arsenic from CCA-treated sawdust. Likewise, chromium removal in F. palustris and L. sulphureus remediation processes was higher than those for C. puteana. This was attributed to low oxalic acid accumulation. These results suggest that F. palustris and L. sulphureus remediation processes can remove inorganic metal compounds via oxalic acid production by increasing the acidity of the substrate and increasing the solubility of the metals.An erratum to this article can be found at 相似文献
12.
Katsumi Togashi Yosuke Taga Kazunobu Iguchi Takuya Aikawa 《Journal of Forest Research》2008,13(2):127-131
Bursaphelenchus mucronatus Mamiya et Enda has been recovered for the first time from adults of the cerambycid beetle, Monochamus urussovi (Fischer), in Hokkaido, Japan. The nematode was also recovered from the inner bark of Picea jezoensis (Siebold et Zuccarini) Carrière and Abies sachalinensis (Fr Schmidt) Masters infested with M. urussovi larvae. PCR–RFLP analysis indicated that B. mucronatus in Hokkaido is the European type. 相似文献
13.
Tomoyuki Nakatsubo Yu Kitamura Norikazu Sakakibara Masaharu Mizutani Takefumi Hattori Nozomu Sakurai Daisuke Shibata Shiro Suzuki Toshiaki Umezawa 《Journal of Wood Science》2008,54(4):312-317
The function of an Arabidopsis thaliana gene, At5g54160 annotated as a caffeic acid O-methyltransferase CAOMT gene was characterized. The recombinant enzyme of this gene (AtOMT1) catalyzed the O-methylation of phenylpropanoid and flavonoid substrates. The specificity constants (k
cat/K
m) for 5-hydroxyconiferaldehyde (5-HCAld) and quercetin were both 0.11 μM−1·min−1. On the other hand, lignins of At5g54160-knockout Arabidopsis mutants lacked syringyl units. In addition, we showed that the gene silencing also resulted in significant accumulation of
caffeyl alcohol (CaAlc). These results strongly suggested that At5g54160 gene is involved in syringyl lignin synthesis for
the methylation of both 5-hydroxyconiferaldehyde and 3,4-dihydroxyphenyl compound(s).
Part of this work was presented at the Annual Meeting of Japan Society for Bioscience, Biotechnology, and Agrochemistry, March
24–27, 2007 相似文献
14.
Natsumi Kanzaki Takuya Aikawa Noritoshi Maehara Yu Ichihara 《Journal of Forest Research》2011,16(4):325-330
The pinewood nematode (PWN) Bursaphelenchus xylophilus is an invasive pathogen that was introduced from North America to Asian countries and Portugal and is devastating native
pine forests. Some native European and Asian Bursaphelenchus nematodes also have weak to moderate pathogenicity to native pine species. To evaluate the potential risk of native Bursaphelenchus species, we inoculated ten Japanese Bursaphelenchus species into native pine species (the dominant forest species) in Japan, and evaluated their pathogenicity using mortality
and tracheal tissue damage as indices. Inoculation was conducted on August 3, 2007, and the symptoms were observed every 2 weeks
until February 1, 2008. None of the inoculated trees, excluding the pathogenic PWN inoculated control, showed external disease
symptoms; however, four species [a less pathogenic PWN isolate, B. luxuriosae, Bursaphelenchus sp. NK215 (undescribed), and NK224 (undescribed)] caused tracheal tissue damage in inoculated seedlings and showed weak pathogenicity.
Therefore, we conclude that there are some potentially pathogenic native species of nematodes distributed in Japan. Interestingly,
two of these weakly pathogenic species, B. luxuriosae and NK215, are not associated with Pinaceae trees, suggesting that nematode pathogenicity may be a pre-adaptive character.
More experimental studies under different conditions are necessary to accurately evaluate the potential risk of these pathogens. 相似文献
15.
Aphidicidal activity of hot and cold water extracts of some indigenous plants, Azadirachta indica A. Juss (neem), Calotropis procera (Aiton) W.T. Aiton (akanda), Polygonum hydropiper L. (biskatali) and Ipomoea sepiaria J. Koenig ex Roxb. (bankalmi), were tested against the bean aphid, Aphis craccivora Koch. Hot water extract of P. hydropiper and A. indica was found to be the most effective (87.6–94.5 and 80.47–89.6% mortality respectively, P < 0.01) among all the extracts. Other hot and cold water extracts also appeared to be useful (59.5–87.5% mortality) as pesticides
for A. craccivora. The highest yield (3.25 kg per plant) was obtained using hot water extract of P. hydropiper followed by hot water extract of A. indica (3.15 kg per plant). The lowest yield (0.32 kg per plant) was recorded from the control block. All the phytoproduct treatments
had significantly (P < 0.01) better yield than the control block. 相似文献
16.
A bark beetle (Ips typographus) infestation caused the death of almost all Norway spruce (Picea abies) trees in a mountain forest in the Swiss Alps. We developed a tree regeneration model, ‘RegSnag’ (=REGeneration in a SNAG stand), to project the future amount and height of tree regeneration in these snag stands. The model combines a height-class structured tree module with a microsite-based module of snag decay and ground-vegetation succession. Microsite-specific rates of germination, mortality and height growth were modelled for four tree species (Picea abies, Sorbus aucuparia, Acer pseudoplatanus and Betula pendula) in eight height classes (from seedlings to saplings 5 m tall) and on 26 microsite types (e.g. moss, grass). Model tests with independent field data from 8 years after the Picea die-back demonstrated that microsites had a considerable effect on the development of tree regeneration on both the montane and the subalpine level. With microsite-specific parameters, the height and frequency of Picea in each microsite could be simulated more accurately than without considering microsite effects (e.g. bias of 8 vs. 119 saplings ha−1 on the montane level). Results of simulations 40 years into the future suggest that about 330–930 Picea saplings per ha out of those that germinated in 1994 and 1996 will reach a height of 5 m within 30–35 years after Picea die-back. This is due to differences in seed inflow and browsing intensities. Picea and not Betula or Sorbus trees will replace the current herbaceous vegetation in these snag stands. 相似文献
17.
Inoculation with edible fungi bestows an added value on mycorrhized plants since production of mushrooms as a secondary crop
can be an economically-valuable resource in forestry management. In order to establish a protocol for controlled mycorrhization
of Pinus halepensis with the edible fungus Lactarius deliciosus, several factors such as fertilisation (35, 60 or 120 mg total N and 13.5, 27 or 54 mg total P), potting substrate (sphagnum
peat or sphagnum peat/vermiculite) and fungal inoculum (mycelial slurry produced in a bioreactor, alginate beads or peat/vermiculite)
were assessed. The most effective inoculum was mycelial slurry at a dose of 10 ml/plant. The two potting substrates assessed
were compatible with mycorrhiza formation. The greatest number of mycorrhized seedlings was obtained with a moderate level
of N (35 mg/plant) or P fertilisation (27 mg/plant). Inoculation did not produce a consistent growth effect on P. halepensis, but seedlings met the quality requirements, making them suitable for planting out. 相似文献
18.
Mycelial growth and mushroom yields of three strains of Pleurotus eryngii produced on wheat bran-supplemented umbrella plant (Cyperus alternifolius) substrate were assessed using surface brightness, bromophenol blue color reactions, ergosterol and glucosamine contents, and water potential as indicators of strain performance. Mycelial growth was 31%–46% greater, depending on strain, on the umbrella plant substrate compared with the mushroom industry standard sugi (Cryptomeria japonica) substrate. Mushroom yields on the first flush were 20%–23% higher, depending on strain, on the plastic bottle-contained umbrella plant substrate. However, yields on the second break were lower from the umbrella plant substrate. Because many growers in Japan only harvest one flush, production of P. eryngii on umbrella plant substrate may offer commercial producers an alternative basal ingredient to diminishing supplies of sugi sawdust.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002. 相似文献
19.
Takanori Imai Sousuke Inoue Naomi Ohdaira Yasuyuki Matsushita Rie Suzuki Mariko Sakurai José Manoel Henriques de Jesus Salete Kiyoka Ozaki Zenesio Finger Kazuhiko Fukushima 《Journal of Wood Science》2008,54(6):470-475
Heartwood extracts from Amazonian trees cumaru-ferro (Dipteryx odorata), jatoba (Hymenaea courbaril), and guarita (Astronium lecointei) exhibit antioxidant activities comparable with that of α-tocopherol, a well-known antioxidant. This article reports the characterization of the antioxidant compounds in the extracts
of the three heartwoods. Silica gel column chromatography of the cumaru-ferro EtOAc extract yielded (−)-(3R)-7,2′,3′-trihydroxy-4′-methoxyisoflavan and (+)-(3R)-8,2′,3′-trihydroxy-7,4′-dimethoxyisoflavan. Silica gel column chromatography followed by preparative high-performance liquid
chromatography of the jatoba EtOAc extract yielded (−)-fisetinidol and (+)-trans-taxifolin. Chemical structures were assigned using electron-ionization mass spectrometry, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy including nuclear Overhauser effect spectroscopy (NOESY), as well as optical
rotation and circular dichroism. Gas chromatography-mass spectrometry demonstrated that the isolated compounds were predominant
in the EtOAc extracts. In the guarita EtOAc extract, catechin and gallic acid were identified by comparing their retention
times and mass fragmentation patterns with those of authentic samples. Antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl
assay demonstrated that all these compounds had activities comparable with that of α-tocopherol.
Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007 相似文献
20.
The antitermitic activities of leaf oils and their constituents, taken from three clones of Eucalyptus camaldulensis Dehnh. in Thailand, against Coptotermes formosanus Shiraki were investigated in contact and noncontact tests. The termiticidal mechanism was also examined. Antitermitic tests
demonstrated that E. camaldulensis leaf oils were both contact toxicants and fumigants to C. formosanus with LC50 values ranging between 12.68 and 17.50 mg/g by the contact method, and between 12.65 and 17.50 mg/petri dish (100 cm3) by the noncontact method. p-Cymene and γ-terpinene were primarily responsible for the contact toxicity and 1,8-cineole was responsible for fumigation.
From the investigation of termiticidal mechanism, E. camaldulensis leaf oils exhibited the inhibition of acetylcholinesterase activity and showed the common symptoms of a neurotoxic mode of
action against C. formosanus.
Part of this report was presented at the 58th Annual Meeting of the Japan Wood Research Society, Tsukuba, March 2008 相似文献