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1.
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
2.
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
3.
The success of tree plantings in agricultural landscapes within dry and variable rainfall regions is often below expectations.
The aims of this study were to investigate techniques for establishing a local native species (Eucalyptus pauciflora) and an exotic species (E. nitens) in the Midlands of Tasmania, a tree-denuded region that has been grazed for over 100 years in Australia. We established
trials at the Sorrel Springs and Woodland Park properties. We compared six establishment techniques: control; understorey
nurse planting; spot burn; mulch; tree-guard and; self-watering tree-guard. Three months, 1 and 6 years after planting we
measured tree height, health index and mortality. At Sorrell Springs tree-guarded treatments had greater height than other
treatments at year one, but there were no effects of treatment at year six on height, health or mortality. At Woodland Park
mulch, burn and tree-guarded treatments had greater height 1 and 6 years after planting. At year six tree-guarded treatments
had lower mortality than other treatments. At Sorrell Springs height of E. nitens was greater than E. pauciflora at year one but not at year six. At Woodland Park height of E. nitens was generally greater at year six but having almost double the incidence of mortality relative to E. pauciflora. We conclude that expensive tree-guarding is only warranted where high browse pressure is expected and that on such sites
species with tough leaves that are resistant to browsing should be considered. Further that in environments marginal for growing
trees, best practice establishment technique is generally as effective as additional treatments of understorey nurse planting,
spot burning or mulching. 相似文献
4.
Comparison and early selection of new clones in <Emphasis Type="Italic">Populus tomentosa</Emphasis>
In our study, two experimental plantations, respectively, with 24 and 32 new clones of P tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height (DBH) of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi. The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically significant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of height, DBH and volume, as well as larger coefficients of variation (CV). The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BT17 and 21J-1 were considered suitable in Weixian. In Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi. 相似文献
5.
Generic equations are proposed for stem, branch and foliage biomass of individual trees in even-aged pure stands of Cryptomeria japonica, Chamaecyparis obtusa and Larix kaempferi. Biomass data was collected from a total of 1,016 individual trees from 247 stands throughout Japan, and five regression
models were assessed by root mean square error, mean bias, fit index (FI), and AIC. The results show that a power equation
using diameter at breast height (dbh) and height is the most suitable for all species and components. This equation is more
accurate than the familiar power equation that uses ‘dbh2 height’, and it expresses the greater volume of branch and foliage mass of trees with a lower height/diameter ratio. A power
equation using dbh is more reasonable for models with dbh as the only independent variable and more accurate than a power
equation using ‘dbh2 height’ for estimating branch and foliage mass. Estimating error for branch and foliage mass is larger than that for stem
mass, but the entire aboveground biomass can be estimated with an error of less than 19%, except in the case of small trees
with dbh less than 10 cm. 相似文献
6.
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
7.
Sprout contribution to natural regeneration of Rhododendron arboreum following the tree felling for fuel wood and other purposes was studied in two disturbed sites (Paipraw and Falockchar) of
Rhododendron forest in Arunachal Pradesh, northeast India. Cut stumps were categorized into seven girth and height classes to evaluate
the effect of stump girth and height on production of sprouts. Effect of stump girth on survival of sprouts was also investigated.
Results show that highest number of cut stumps is recorded in medium girth classes (50–80, 80–110, and 110–140 cm) in both
Paipraw and Falockchar stands. However, density of cut stumps is higher in Paipraw (1 210 stumps·ha−1) than Falockchar (1 154 stumps·ha−1). Nevertheless, a little higher percentage of sprouting is recorded in Falockchar (18%) than that of Paipraw (15%). Similarly,
maximum number of cut stumps is observed in the medium height classes (50–80, 80–110 and 110–140 cm) in both the sites. Cut
stumps with lower girths show greater ability of sprouting than that of larger girth classes. Significant correlations are
observed between stump girth and sprout number and between stump height and number of sprouts. Survival of sprouts also depends
on stump girth. Survival of sprout shows significant variations between different sampling times in both the sites. Though
overall sprout regeneration of R. arboreum is very poor, sprouts arising from lower girth classes survive well than those of higher girth classes. The findings of this
investigation signify that stump sprouting is not playing much role in the natural regeneration of R. arboreum though it has the ability to sprout. Sprout survival is not adequate to restore a stand where indiscriminate tree felling
is continued and the species may be considered as a poor coppicer. Therefore, regeneration through seeds and seedlings should
be preferred over regeneration through sprouting. 相似文献
8.
Deyang Liang Changjun Ding Guanghao Zhao Weiwei Leng Min Zhang Xiyang Zhao Guanzheng Qu 《林业研究》2018,29(3):611-622
Understanding genetic variation is important for efficiently selecting excellent clones and utilizing genetic resources during tree breeding. We investigated 16 growth traits of 50 32-year-old Pinus koraiensis clones. Analyses of variance showed that all the test traits differed significantly among clones. Average height, diameter at breast height (DBH), and volume of all clones were 10.41 m, 21.30 cm, and 0.148 m3, respectively. Phenotypic coefficients of variation and repeatabilities of traits ranged from 4.37 to 48.03% and from 0.013 to 0.900, respectively. There exists significant positive correlations among heights, diameter at different heights (1.3, 3.0, 5.0 m), and volumes; genetic correlation was close to phenotype correlation. Using four growth traits (height, DBH, volume, average crown width) as indices for a comprehensive evaluation, five clones (PK 11, PK 19, PK 04, PK 14, and PK 28), whose traits scored in the top 10%, were selected as elite clones. For these clones, genetic gains in height, DBH, volume and crown height were 8.58, 13.02, 32.72 and 3.83%, respectively. These results provide important information for improving P. koraiensis breeding programs. 相似文献
9.
Sadao Takaoka 《Agroforestry Systems》2008,72(3):169-172
This study examined the long-term growth performance of Cordia africana and Grevillea robusta, which are the most common indigenous and exotic trees, respectively, associated with crops in the Mount Kenya region. Local
farmers prefer G. robusta to C. africana as on-farm trees because they believe that G. robusta grows faster. Measurements of height and diameter at breast height were made of 47 C. africana and 89 G. robusta trees for which the age was established based on interviews with farmers. The oldest G. robusta and C. africana trees were 55 and 46 years old, respectively. The apical growth rate for G. robusta was greater than that for C. africana in Katheri (a humid area). The differences between the two species were less remarkable in Ruiri (a dry-subhumid area). There
was no notable difference in the radial growth performance of the two species in Katheri and Ruiri. These comparisons suggest
that the long-term growth performance of C. africana is not necessarily inferior to that of G. robusta. 相似文献
10.
Michal Hejcman Lukáš Strnad Pavla Hejcmanová Vilém Pavlů 《Journal of pest science》2012,85(2):191-198
Several authors record high mortality of the weedy species Rumex obtusifolius in unmanaged grasslands, but there have never been any studies on how the performance and mortality of R. obtusifolius and R. crispus are affected by different nutrient availability in unmanaged temperate grasslands. To investigate this question, we established
a seedlings transplantation and fertiliser experiment on unmanaged Dactylis glomerata grassland in Czech Republic. We monitored plant height, number of leaves per plant, fertility and mortality of transplanted
R. obtusifolius and R. crispus plants, from 2008 to 2011, in an unfertilised (U) and a fertilised (F) treatment (manure applied in 2008 at the rate of 200 kg
of nitrogen, 42 kg of phosphorus and 230 kg of potassium per ha). In 2010, taller plants of both species were recorded in
treatment F than in treatment U, but there was no effect of treatment on the number of leaves. In 2010, fertility for both
species was 50% in treatment F, but only 20% for R. obtusifolius and 10% for R. crispus in treatment U. Over 4 years, no mortality of R. obtusifolius in treatment F contrasted with 30% mortality in treatment U. In the case of R. crispus, mortality was 50% in treatment F and 28% in treatment U. An increase in nutrient availability can decrease mortality of
R. obtusifolius plants in grasslands, but increase mortality of R. crispus. It seems that leaving grassland unmanaged for several years is only an effective strategy for control of R. obtusifolius under conditions of low nutrient availability. 相似文献
11.
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
12.
Robert Brus Dalibor Ballian Peter Zhelev Marija Pandža Martin Bobinac Jane Acevski Yannis Raftoyannis Kristjan Jarni 《European Journal of Forest Research》2011,130(4):657-670
We examined leaf and mature seed cone variation of Juniperus oxycedrus L. subsp. oxycedrus in 12 natural populations across the species range in the Balkan Peninsula. We measured 10 morphological traits from a minimum
of 100 leaves in each of 190 individuals, and two morphological traits from 30–50 seed cones in each of 94 females. High phenotypic
variation was found, but no geographical structure or cline across populations was detected for any of the studied traits.
Mean values of comparable leaf and cone morphological traits did not differ considerably from values reported elsewhere. Gender
dimorphism in leaf morphology was detected, but it was not distributed uniformly throughout the studied area. An ANOVA model
with both nested and crossed effects revealed that the largest proportion of the total variation was, as expected, contained
within populations, partly as among-tree variation (18–47%, depending on the trait) and partly as within-tree variation (33–77%),
which was remarkably high. Gender dimorphism explained only 0–3% of the total variation. Differences among populations (2–23%)
were significant for all studied traits except one; however, PCA showed no clear geographical differentiation of the studied
populations. This lack of phylogeographical structure may be the consequence of repeatedly occurring colonisation-retreat
scenarios and suggests the existence of several small refugial populations scattered over a large part of the Balkan Peninsula
in the Pleistocene. Further research including palaeobotanical and molecular genetic studies will be needed to better understand
the forces that shaped current variation patterns of J. oxycedrus L. subsp. oxycedrus in the Balkan Peninsula. 相似文献
13.
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
14.
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
15.
Maman?Turjaman Yutaka?Tamai Hendrik?Segah Suwido Hester?Limin Joo Young?Cha Mitsuru?Osaki Keitaro?Tawaraya
Trees of the family Dipterocarpaceae are the dominant trees in Southeast Asian tropical forests where they play an important ecological role and are also important commercially. An experiment was conducted to determine the effect of ectomycorrhizal fungi on the growth of dipterocarp species in peat soils. Seedlings of Shorea pinanga were inoculated with spores of two ectomycorrhizal fungi, Pisolithus arhizus and Scleroderma sp. were grown in pots containing sterilized peat soil for 7 months. The percentage of ectomycorrhizal colonization on S. pinanga exceeded 86%. Colonization of S. pinanga roots by ectomycorrhizal fungi resulted in increased shoot height, stem diameter, number of leaves, and shoot fresh and dry weight. Survival rates of S. pinanga were greater for inoculated seedlings than control seedlings. These results suggest that inoculation of ectomycorrhizal fungi can improve the early growth of S. pinanga grown in tropical forests and that this technique will accelerate the rehabilitation of degraded dipterocarp forests. 相似文献
16.
Eighteen clones of Eucalyptus tereticornis (Sm.) were evaluated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab,
India and compared with two checks. Significant variations were recorded for height, diameter at breast height (DBH) and clear
bole height (CBH). The broad sense heritability was low to moderate for both height and CBH. The genetic gain for height and
CBH increased substantially per se with the increase in age of trees. The average genetic gain for three years was recorded maximum for height (159.60%) followed
by DBH (110.97%) and CBH (70.34%). Clone 17 attained maximum DBH over other genotypes for second and third year followed by
clones 14 and 11. Clone 5 showed an upward trend for DBH and maintained its superiority for CBH as the age of the tree increased.
Similarly, clone 11 changed its ranking from 9th to 8th to 3rd for DBH and from 9th to 4th to 2nd for CBH, respectively for
the age of one, two and three years. Nonetheless, clones 6 and 10 performed poorly for all the characters studied. Clones
17, 14 and 5 were found to be the most promising clones for commercial deployment. 相似文献
17.
To investigate genotype by environment interaction (G×E) for clones of radiata pine (Pinus radiata), clonal stability was
evaluated for growth and form traits from three trials in New Zealand and three trials in Australia. There were 215–245 clones
in common between pairs of New Zealand trials, 17–26 clones in common among Australian trials, while 32–52 clones were in
common between New Zealand and Australian sites. Clonal repeatability ( [^(H)]2 ) \left( {\hat{H}^{2} } \right) and type-B genetic correlations were estimated. The general trend across the six trials for clonal repeatability was that
[^(H)]2 \hat{H}^{2} was greatest for height (HGT) followed by diameter at breast height (DBH), stem straightness (STR), and branch quality score
(BRQ). Within New Zealand trials, there was little evidence of G×E for growth traits, but more for form traits. For DBH the
average type-B genetic correlation within New Zealand was 0.82; and for HGT, the average type-B genetic correlation within
New Zealand was 0.76. Within Australia, there was only one statistically significant type-B genetic correlation for DBH and
this estimate was high indicating that clonal ranks were similar on these two trials. Additionally, within Australia and between
regions type-B genetic correlations were generally high for form traits, at least for STR. One Australian trial (Trial 5)
showed relatively high clonal stability with the three trials in New Zealand indicating that the ranks of these clones were
relatively stable in both regions. From a clonal testing standpoint, these results suggest that stable clones can be identified
that perform well in both New Zealand and Australia. Improvements in both growth and form traits can be expected when radiata
pine clones are transferred between Australia and New Zealand within regions similar to those sampled in this trial series. 相似文献
18.
H. S. Ginwal 《New Forests》2010,40(2):205-212
A provenance cum progeny trial comprising 13 provenances and 91 families of Eucalyptus tereticornis Sm. of Australian and Papua New Guinean (PNG) origin was laid out in India in 2002. In one family emanating from CSIRO seed
lot no. 13418, (tree no. DS000141) Sirinumu Sogeri Plat, PNG cleistogamy was observed earlier. This trait appears to be under
genetic control, and presumably results in obligate selfing. In the present study, the effect of forced selfing, was examined
in this family after 48 months of field planting. Severely depressed seed set, germination percent, field growth and survival
in relative comparison to other out crossing families was noticed. Inbreeding depression was noticed in growth traits viz.
height, clean stem height, DBH, branching and survival per cent, which increased with age. High coefficient of variation was
observed in family bearing cleistogamous flowers than the other predominantly out-crossed families. 相似文献
19.
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
20.
Brenda Colleen Clifton-Cardoso Marcelo Schramm Mielke José Roberto De Melo Rondinele Nascimento Querino 《New Forests》2008,35(1):15-31
Dimorphandra jorgei MF Silva (Caesalpinaceae) and Swartzia macrostachya Benth. var. riedelii Cowan (Fabaceae) are tree species from the southern Bahian Atlantic Forest, identified for the restoration of degraded areas.
The objective of this research is to study their seed germination and seedling growth to develop simple methods for seedling
production in small scale nurseries. Because the species have distinct dormancy and germination characteristics, the seeds
were submitted to different treatments. D. jorgei seeds were immersed in hot water, scarified and stored for 12 weeks in the laboratory environment (25°C). S. macrostachya seeds were submitted to different combinations of drying and storage in the laboratory environment or refrigerator (4°C).
Seedlings were submitted to two light treatments for 3 months: partial shade (52% of full sun) and full shade (12% of full
sun). In D. jorgei, the highest germination occurred for scarified seeds (87%) and for seeds stored for 12 weeks and then scarified (69%). In
S. macrostachya the undried control seeds had the highest germination, followed by that of the refrigeration storage treatment, without predrying
(99% and 97%, respectively). The average values for the growth parameters were greater in full shade for D. jorgei, while S. macrostachya seedlings showed greater growth rates in partial shade. Two months growth is recommended before D. jorgei seedlings are of the sufficient size and leaf number for field planting. On the other hand, a period of 4 months is recommended
for S. macrostachya, due to its relatively slow growth. 相似文献