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1.
Only recently have efforts begun to address how management might prepare currently healthy forests to affect the outcome of
invasion by established non-native pests. Cronartium ribicola, the fungus that causes the disease white pine blister rust (WPBR), is among the introductions into North America where containment
and eradication have failed; the disease continues to spread. Ecosystem function is impaired by high rust-caused mortality
in mature five-needle white pine forests. This paper evaluates five proactive management options to mitigate the development
of impacts caused by white pine blister rust in threatened remote high-elevation five-needle pine ecosystems of western North
America. They are: reducing pest populations; managing forest composition; improving host vigor; introducing resistant stock
with artificial regeneration; and diversifying age class structure to affect the natural selection process for resistance.
Proactive intervention to manage and facilitate evolutionary change in the host species may sustain host populations and ecosystem
function during pathogen naturalization. 相似文献
2.
《Scandinavian Journal of Forest Research》2012,27(1-4):406-409
The host alternation of Melampsora larici‐epitea occurring on Salix burjatica in experimental short‐rotation cultures in Finland was studied by inoculation tests. Larix sibirica was tested as the most probable alternate host. It was inoculated with rust basidiospores, and the life cycle of the pathogen was succesfully completed by inoculating the willow with aeciospores developed on larch needles. 相似文献
3.
The association between blue stain fungi andIps cembrae Heer (Coleoptera: Scolytidae) was investigated in the Japanese larch,Larix leptolepis Gordon, in the Nagoya University Forest, Aichi Prefecture, central Japan.I. cembrae had one or two generation(s) in a year in this study area. Two blue stain fungi,Ophiostoma piceae andLeptographium sp., were isolated from the body surface of both male adults in mating chambers and female adults in parent galleries, suggesting
that this beetle species was a vector of these fungi. Although no blue stain fungi were isolated from non-stained wood, both
fungi were isolated from the mating chambers, the center and the uppermost end of the galleries throughout the season. The
fact thatO. piceae was consistently isolated with high frequency from adults and from their galleries strongly suggested that this species would
be the principal blue stain fungus infecting the beetle-attacked larch trees. 相似文献
4.
The paper summarized the life cycle, environmental features and distributions ofLarix origination in Japan. The time of blooming and fruiting and the ways of cone collection and seeds storage were introduced.
The treating methods of seeds germination and the sowing time for both Japanese larch (Larix kaempferi Carr) and Dahurian larch (Larix gmelinii var.japonica Pilger) were discussed.
Responsible Editor: Zhu Hong 相似文献
5.
In this study, the pathogen and parasite spectra of Turkish populations of the great spruce bark beetle Dendroctonus micans (Kugelann) (Coleoptera: Curculionidae, Scolytinae) are analysed. In addition to the previously studied infective green alga
Helicosporidium, three more pathogens and parasites, i.e. the yeast Metschnikowia sp., the neogregarine Mattesia sp. and a nematode, were recorded here for the first time. The pathogens and parasites occur in different quantities and
combinations in outbreaks of the beetle at five Turkish localities. 相似文献
6.
The objectives of this study were (1) to evaluate the effects of environmental factors derived from GIS on tree-height growth
of Japanese larch (Larix kaempferi) and (2) to develop a best-fit regression model for its site index. Based on data from 40 sample plots situated in an even-aged
(38 years), pure, and undamaged Japanese larch stand, multiple regression models for a site index of Japanese larch were constructed
using environmental factors as independent variables. The average slope gradient, effective relief, distance from ridge, flow
accumulation, degree of exposure, shading, solar radiation index, and gravitational water index were used as environmental
factors and calculated on GIS using digital elevation model data. These factors were related to the Japanese larch site index
through multiple-regression analysis. The result showed that the most effective factor for estimating site index was the degree
of exposure. Through a backward stepwise procedure, the degree of exposure, shading, and average slope gradient were selected
for a best-fit regression model. This model explained 72% of the variance in site index, with standard error estimates of
1.75 m. This strong relationship suggests that GIS-derived environmental factors can be used to predict site indices of Japanese
larch.
This study was supported by the experimental forest of Kyushu University. 相似文献
7.
[目的]通过对落叶松种间及其杂种生长与形质性状评价来定向选育优良落叶松建筑材。[方法]以辽宁省大孤家林场32年生的落叶松试验林为实验材料,对落叶松属日本、兴安、长白及华北4个落叶松种,及以日本落叶松为母本的日本×兴安、日本×华北、日本×长白、日本×日本杂种的生长和形质性状进行变异规律分析,并采用模糊数学隶属函数对其差异显著指标进行综合评价。[结果]表明:落叶松种和杂种间生长差异显著(p<0.01),杂种胸径、树高和材积总生长量与母本差异不显著,却显著高于相应父本;杂种之间的生长差异体现在林分的前10年,随着林龄的增大优势逐渐减退;树冠特征因子中的枝下高、冠长、枝条直径、长度、角度和干形特征因子中的高径比、树干圆满度、节子直径、长度、角度在落叶松种和杂种间差异显著。基于上述指标进行了生长和形质性状综合评价,排名前三位的分别为日本×兴安、日本×长白和日本落叶松。32年生时日本×兴安的胸径、树高和材积分别为18.69 cm、21.62 m和0.339 2 m3;日本×长白的为18.44 cm、23.85 m和0.339 6 m3;日本落叶松的为19.36 cm、21.31 m和0.335 7 m3;而且它们在适应性上也具有明显优势。[结论]日本×兴安、日本×长白和日本落叶松适合作为定向培育建筑材的优良品种在东北地区重点推广。 相似文献
8.
Masashi Ohsawa Yoshio Kuroda Mitsutoshi Tsunoda Keizo Katsuya 《Journal of Forest Research》1996,1(2):107-110
Damage caused by stem-rot and the progress of the causal fungi in old-aged Japanese larch (Larix kaempferi (Lamb.) Carr.) was investigated at the foot of Mt. Fuji. Stem-rot was found in 75% of 108 trees investigated, and volume
of rot was 6% of the total wood volume in the forest investigated. Stem-rot damage was much greater than the damage by butt-rot.Stereum sanguinolentum (Alb. and Schw. ex Fr.) Fr. infected larch trees at the greatest incidence (49.4%). However,Porodaedalea chrysoloma (Fr.) Imaz. caused the most volume loss to the trees.S. sanguinolentum infected larch stems mainly through stem wounds, and decay caused by the fungus progressed 9.75×102 cm3/year on average.P. chrysoloma infected larch stems mainly through dead branches and wounds, and the average rate of decay progress for the fungus was 2.74×103 cm3/year. 相似文献
9.
Nobuhiro Akashi 《Journal of Forest Research》2006,11(3):153-156
The effect of browsing frequency by Sika deer (Cervus nippon yezoensis) on the height growth of Japanese larch (Larix kaempferi) in Hokkaido, Japan, was analyzed. Tree heights at the time of the census and at the start of the current growing season
were determined for 100 trees selected randomly at each site. The tallest shoot on each tree was identified and the number
of browsing occurrences on the current-year shoot was determined. Young larches browsed by deer repeatedly develop new shoots
during a growing season. Larch is a browsing-tolerant species, and the average height growth of the most heavily browsed trees
was >15 cm. Although resprouting partly compensated for decreased height growth caused by browsing, the annual increase in
height decreased with increased browsing frequency. Thus, browsing frequency during a growing season best reflects the intensity
of browsing damage to larch trees. 相似文献
10.
Eiji Hayashi Kazuya Iizuka Shin-ichi Sukeno Kohzo Kohno 《Journal of Forest Research》1998,3(2):119-122
We determined the survival rate of tree families produced by the intra- and interspecific crossing of larch species damaged
by browsing of vole (Clethrionomys rufocanus bedfordiae Thomas) and the contents of ether extracts (EE) in their bark. The average survival ofLarix gmelini var.japonica Pilg. (L. gmelini)×L. gmelini (G×G) was highest, followed by the hybridL. gmelini×L. leptolepis Gordon (G×L). The families of the hybrid G×L, which is considered suitable for silviculture in Hokkaido, Japan, showed significant
differences in survival rates, suggesting that it is possible to produce improved varieties of the hybrid which are more resistant
to vole browsing. The EE contents of the bark were under strong hereditary control, and the rank of the EE content among the
various families hardly fluctuated between the location of the test fields. The correlation coefficient between the survival
rates and the EE contents was highly significant (r=0.89,n=24,p<0.01), indicating that the EE content in the bark may be used as a possible index of resistance or susceptibility to vole
browsing in larch plantations.
A part of this report was presented at the 106th Annual Meeting of the Japanese Forestry Society, at Sapporo, April, 1995. 相似文献
11.
Dahurian larch (Larix gmelinii Rupr.) Rupr is one of the dominant species in both natural and man-made forests in northeast China. Effects of site factors,
including topography, soil properties and nutrient elements (P, Ca, K, Mg, Mn, Zn, Cu, Ag, Co and Ni) on the growth of larch
were analyzed in detail, qualitatively and quantitatively. The ordination technique was used to group the site factors and
to classify sites for larch. Analysis indicated that height growth, diameter (DBH) and volume of the larch varied among site
types and this will be of theoretical and practical significance in developing larch plantations. 相似文献
12.
Marcelo de Carvalho Alves Fábio Moreira da Silva Edson Ampélio Pozza Marcelo Silva de Oliveira 《Journal of pest science》2009,82(2):137-148
The advent of Precision Agriculture has made possible the analysis of complex spatial patterns of plant disease epidemiology
considering statements of integrated disease management. The objective of this work was to use geostatistics, statistics and
geographical information systems to characterize the structure and magnitude of spatial dependency of rust (Hemileia vastatrix) and brown eye spot (Cercospora coffeicola) incidence and severity in coffee agroecosystem cultivated with Catuai Vermelho IAC-99 (Coffea arabica L.). Evaluations of incidence and severity of rust and brown eye spot were accomplished at 67 georeferenced points arranged
in 6.6202 ha of coffee crop, in the years of 2005, 2006 and 2007. Exponential models of covariance enabled the characterization
of the magnitude and structure of rust and brown eye spot spatial variability in the evaluated dates. Ordinary block kriging
presented satisfactory performance to map rust and brown eye spot outbreaks based on kriging error coefficients. Kriged maps
enabled the visualization of intensity of rust and brown eye spot in each evaluation date. Assessments of incidence and severity
presented highly statistical correlation based on linear regression models, also confirmed by the spatial variability of kriging
maps. Kriging maps of rust and brown eye spot enabled to observe that intensity of disease was dispersed in foci patterns
along the coffee plantation, indicating that the current strategy of disease control based in total area may be replaced by
site specific disease management, with less environmental impact and sustainability of coffee crop, according to statements
of integrated disease management and precision agriculture. 相似文献
13.
The period between 2000 and 2002 repeated outbreaks of the web spinning sawfly Cephalcia lariciphila (Wachtl 1898) around the village of Větrny Jeníkov, Czech Republic. The impact of defoliation, caused by C. lariciphila feeding, on tree-ring formation of European larch (Larix decidua Mill.) was studied using dendrochronological methods. Heavy defoliation resulted in much less growth in the years of insect attack, the average incremental loss being 67% for the 2000–2002 period. Also, defoliation resulted in the formation of latewood with fewer cells and reduced cell-wall thickness. 相似文献
14.
Alexandra Sasha Nikolaeva Maggi Kelly Kevin L. O’Hara 《Journal of Sustainable Forestry》2019,38(5):471-485
The Forest Stewardship Council (FSC) aims to promote environmentally responsible forest management globally. However, quantifiable evidence of effects of FSC on forest management practices is lacking. FSC has been present in the Russian forestry arena for over 20 years. In this case study, we compare ecological indicators of forest management in FSC-certified and non-certified companies in Primorsky Krai of the Russian Far East. Those indicators include percent of forest cover loss and gain on forest concessions managed by three certified and three non-certified companies. We also interview a range of stakeholders involved with forest management or in forest policy planning in Russia to provide context for this case study. Results indicate no difference between certified and non-certified companies with regard to forest cover loss from 2008 to 2015 or forest cover gain from 2000 to 2012. Stakeholder interviews reveal that while forest certification is viewed positively and considered an efficient mechanism to improve forest management, the stakeholders doubt its ability to stimulate quantifiable changes in forest management practices in Russia and the Far East specifically. We focus on Primorsky Krai because of its unique geographic location, where its neighbors China and Japan significantly influence Primorsky Krai’s export market. 相似文献
15.
Resistance of the Japanese larch (Larix kaempferi) (Lk), the Kurile larch (L. gmelinii var. japonica) (Lg), and their F1 hybrid (Lg × Lk) to bark stripping by sika deer (Cervus nippon yesoensis) were studied in a forest in Hokkaido by cafeteria tests. Several sets of logs prepared from Lk, Lg, and Lg × Lk were fed to the deer. The stripped areas of logs significantly differed between the Lk/Lg set and the Lk/Lg × Lk set (P 0.05). The resistances of Lg and Lg × Lk to bark stripping was stronger than Lk. This result was similar to those of previous studies on gray-sided voles and mountain hares in Hokkaido. 相似文献
16.
Mayumi Sato Kazuto Seki Kazuhito Kita Yoshinari Moriguchi Makoto Hashimoto Keita Yunoki Masao Ohnishi 《Journal of Wood Science》2009,55(1):32-40
The diterpene compositions in the bark of branches were investigated for two families of the F1 hybrid, Kurile larch (Larix gmelinii var. japonica Pilg.) × Japanese larch [Larix kaempferi (Lamb.) Carr.] (hereafter F1) and their parents clones. 13-Epimanool, larixol, larixyl acetate, 13-epitorulosyl acetate (not detected in L. gmelinii var. japonica), isopimaric acid, abietic acid, dehydroabietic acid, and neoabietic acid were detected. Larixol and abietic acid represented
more than 50% of the diterpene content in L. gmelinii var. japonica and L. kaempferi, respectively. Larixol and abietic acid were the predominant diterpene components in the F1, and the proportions of these diterpenes were between those of the parental species. Therefore, the diterpene compositions
in the F1 were hereditarily infl uenced by their parents. The ratios of labdane, pimarane, and abietane diterpenes suggested that the
main diterpene biosynthesis pathway in L. gmelinii var. japonica was from copalyl diphosphate (CDP) to labdane-type diterpenes, and that in L. kaempferi was from CDP to abietane-type diterpenes via pimarane type. Furthermore, linear discriminant analysis suggested that the
diterpene contents are effective indices for the discrimination of the hybrid seedlings.
Part of this article was presented at the Annual Meetings of the Japan Society for Bioscience, Biotechnology, and Agrochemistry
in Kyoto, March 2006, and in Tokyo, March 2007 相似文献
17.
The aim of this study is to evaluate the recruitment possibilities of holly (Ilex aquifolium L.) populations under Pinus sylvestris plantations in the mountains of Central Spain. Population recruitment of holly under P. sylvestris L. plantations was studied at two localities. We sampled holly seed rain, seed bank, and seedling emergence and survival (of both emerged and planted seedlings) in both localities. Seed germination was analysed by randomly sowing Ilex seeds and their subsequent recollection and analysis over the following 3 years (only in one locality). Seed rain, seed bank and emerged seedling densities did not differ between localities. Seed bank density was between 10 and 20 seeds m−2, considerably higher than the observed seed rain (0.4–1.2 seeds m−2), and also higher than the emerged seedling density (0–4 seedlings m−2). But Ilex is not very efficient in germinating under pine forests (29.1% germination after 3 years). This may indicate a seed accumulation process of at least 5 years. Seedling survival for the first year differed among the studied sites (50–60 vs. 17%). Nevertheless these survival rates are higher than those found for the same seedling populations in different forest habitats (not Scots pine forests) from near locations. Differences in summer water stress between the study sites are proposed as the main cause of the observed differences in seedling survival. It is concluded that P. sylvestris forests may provide one of the best regeneration habitats for holly in the Mediterranean area, where this species is close to the Southern limit of its distribution. 相似文献
18.
G. Georgiev 《Journal of pest science》2005,78(3):161-165
The major bioecological characteristics of Bracon intercessor Nees (Hymenoptera: Braconidae), a parasitoid of the poplar clearwing moth, Paranthrene tabaniformis (Rott.) (Lepidoptera: Sesiidae), were studied from 1987 to 2003. Poplar shoots infested with P. tabaniformis larvae were collected in 11 localities in Bulgaria and examined in the laboratory, and infestations were also studied in the field. B. intercessor was recorded in seven localities and was found to be a gregarious external larval parasitoid of P. tabaniformis. Two generations of the parasitoid developed on the host. The first (summer) generation was associated with early and mid-stage (up to third instar) host larvae, and the second (overwintering) generation with third- to fifth-instar larvae. The average number of parasitoid individuals feeding on a host was 4.5 and 12.4 in summer and overwintering generations, respectively. The maximum number recorded was 25 individuals per host in the overwintering generation. B. intercessor overwintered as a mature larva on the host and completed its development in early spring. The adults from the overwintering generation appeared in April, about 1 month prior to emergence of P. tabaniformis. The life cycle of B. intercessor was not in close synchrony with the development of P. tabaniformis in the spring, but the parasitoid adults which fed on honey-sugar solution lived for up to 31 days (males) and 86 days (females), respectively. This suggests that, in the field, B. intercessor females eclosing in the spring could survive until the host larvae appear if nectar is available. Adults of the summer generation emerge from July to September when sufficient suitable host larvae are available. B. intercessor was responsible for 1.5% of the average mortality of the P. tabaniformis overwintering larvae. The host mortality caused by the summer generation of the parasitoid ranged from 3.2% to 5.8%. 相似文献
19.
Reflectance features of water stressed Larix gmelinii needles 总被引:1,自引:0,他引:1
Lei Wang You-qing Luo Hua-guo Huang Juan Shi Kari Keliövaara Wen-xia Teng Guo-xin Qi 《中国林学(英文版)》2009,11(1):28-33
In recent years, Xing’an larch (Larix gmelinii) has been seriously infected by pests and drought. In order to improve the accuracy of monitoring the damage to larch by remote sensing (RS) and to predict the health of the larch, we studied the reflectance features of larch needles under different water conditions at the needle level by using the LIBERTY (Leaf Incorporating Biochemistry Exhibiting Reflectance and Transmittance Yields) model. Before applying the LIBERTY model, we recalibrated it for the needles of L. gmelinii based on ten field-measured spectral curves. After recalibration, LIBERTY can accurately model the needle reflectance spectra of L. gmelinii. Based on the recalibrated LIBERTY model, we extracted and analyzed the sensitive bands to needle water content by simulating the needle reflectance spectra under different drought conditions. Then, we established mathematical equations between the spectral indices (MSI, NDWI, and GVMI) and needle water content. Results show that the variations of larch needle water content can significantly change the needle spectra at the near-infrared and short-wave infrared bands. The higher the water content is, the higher the absorption peak is. We believe that our study will provide the theoretical basis and an optional method to investigate the forest water stress using multi-spectral or hyper-spectral remote sensing data. 相似文献
20.
Melampsorella caryophyllacearum is a heteroecious fungus that produces disease on silver fir resulting in galls that depreciate the value of trees. Currently,
little is known about its epidemiology. The purpose of this study was to identify those site or management factors associated
with fir broom rust infection. A 29-plot systematic sampling was carried out throughout all silver fir forests in the Spanish
Pyrenees. In every sampling plot, we examined each tree for the presence of M. caryophyllacearum galls or witch’s brooms. We differentiated their position as either on the main stem or on the branches of trees. We identified
the most susceptible stands by relating a compendium of tree and stand variables with the presence and severity of symptoms.
Disease symptoms were observed in 11.8% (95% CI: 5.8–17.9%) of trees. Fir broom rust-infected trees tended to be those of
larger diameters. The rust infection was observed in 55.2% (95% CI: 35.7–73.6%) of the stands. We identified a wide range
of severities with 5 of 29 stands having more than 30% of trees infected. Fir broom rust appeared to be a widespread disease,
although we observed important differences in terms of severity. The presence and severity of the rust in stands was associated
with understories composed of more shade tolerant plant species and with longer periods without thinnings. Canopy opening
should be experimentally tested as a possible control method. 相似文献