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1.
RAPD analysis on genomic DNA of male and female plants of Acer negundo L.   总被引:1,自引:0,他引:1  
IntroductionRAPDisawidelyadoptedmolecularbiologicaltechniqueinmanyfieldsincludingforestry.J.1.Hormazaetsl.(1994)appliedthistechniquetosexrelatedresearchondioecioustreespeciesPistsciaveraL.andresultedverywell.Arandomprimerthatproducesspecificamplificationsolelyforfemaleplantwasscreened.Itwassupposedthespecificamplificationwascloselylinkedtofemafesexcontrolgene.AndtherandomprimerwasprovedapplicabletoseedlingsexidentificationofPiStscisveraL.bysystematicalexperiments.ApreliminarystudyonAcerne…  相似文献   

2.
Inonotus rickii was detected for the first time causing cankers and decay in Acer negundo and Celtis australis in Italy. In a boxelder boulevard, declining trees showed sparse foliage, exudations and cracks in the bark; in some cases, chlamydospore masses were present. Five isolates were collected and compared by growth tests in vitro and electrophoretic analyses; three isolates from the same boulevard showed very similar physiological characters. The increasing importance of the pathogen in urban areas is underlined and discussed.  相似文献   

3.
This research subjected four wood species pigmented with the red stain of Scytalidium cuboideum and Acer negundo wood pigmented with the tree’s naturally occurring red stain to natural and artificial UV light. Several commercially available coatings were applied to determine the effect of coating on the degradation of both red stains over time. The red stain of Acer negundo was found to be significantly less stable in UV light than the red pigment produced by S. cuboideum on any wood species, even A. negundo. None of the tested coatings significantly increased the pigment retention time of the red stain produced by A. negundo. The red stain of S. cuboideum was significantly affected by both coating and wood species; Populus tremuloides retained pigment significantly longer than Fagus grandifolia or Acer saccharum, and the Danish oil coating retained pigment significantly longer than the lacquer, water-based polyurethane with UV inhibitors, or the uncoated samples. Overall, lacquer increased the degradation rate of the red pigment produced by S. cuboideum, with the most pronounced increase occurring on F. grandifolia. These results indicate that the red-pigmented wood produced by A. negundo may not be appropriate for applications involving UV exposure, regardless of coating utilized. However, P. tremuloides wood pigmented with S. cuboideum may be appropriate for such applications, especially if Danish oil is applied as a coating.  相似文献   

4.
以复叶槭的茎段、叶片为外植体,以MS为基本培养基,附加多种激素配比试验,结果表明:叶外植体在各种培养基上均形成愈伤组织,但没有出现芽的分化。茎段外植体在多种培养基上均产生愈伤组织,但仅在MS+0.000 5mg.L-1TDZ+0.01 mg.L-1NAA培养基上出现再生芽,芽的分化率为22.8%,在MS+0.1 mg.L-1NAA上生根率为83.3%,移植后成活率为86.2%。  相似文献   

5.
Boxelder (Acer negundo) is planted as ornamental and shade tree in many countries including Iran. During July 2016, boxelder trees in parks and streets of different localities in East Azarbaijan province, Iran were found to be heavily infected with powdery mildew. Whitish powdery fungal mass developed mainly on the lower leaf surface. The infected young leaves became bubbled, curled and crinkled, giving affected plants an unpleasant appearance. During September, scattered, dark brown, spherical chasmothecia were produced on the lower leaf surface. The causal agent was identified as Sawadaea negundinis based on a combination of morphological characteristics of sexual and asexual morphs and sequence data of the rDNA internal transcribed spacer region (ITS1‐5.8S‐ITS2). This study provides the first report on the occurrence of S. negundinis on boxelder in Iran.  相似文献   

6.
Epicoccum purpurascens, a component of the bark micromycota, was evaluated as a potential biocontrol agent for three decay‐causing hymenomycetes frequently found in Buenos Aires city trees, Ganoderma platense, Inonotus rickii and Rigidoporus ulmarius. Treatments consisted of dual cultures of E. purpurascens and xylophagous fungi on box elder (Acer negundo) wood blocks. Two inoculation sequences were tested: (i) the biocontrol agent as the first microorganism inoculated followed by the pathogen; and (ii) the xylophagous fungus as the first microorganism inoculated followed by the biocontrol agent. After 3 months of incubation, percentage dry weight loss was calculated. When E. purpurascens was allowed to colonize wood blocks before the introduction of the xylophagous fungus, dry weight loss was significantly reduced in all instances. However, as a secondary colonizer, E. purpurascens mildly reduced the weight loss caused by G. platense, had no effect on degradation by I. rickii and increased wood weight loss by R. ulmarius.  相似文献   

7.
Cellulase activities of Anoplophora glabripennis (Motsch.) adults from two host plants (Populus simonii × P.pyramidliscr cv.Opera Hsu.and Salix matsudana Koidz) fed on three different host tree species (Acer negundo Linn.,S.matsudana Koidz and P.simonii × P.pyramidliscr cv.Opera Hsu.) were investigated.Enzyme activities of endoglucanase and β-glucosidase in the intestines of the insects were measured.The results show that there are no statistically significant differences in the enzyme activities of endoglu...  相似文献   

8.
The extensive flooding by the river Rhine on May 12 1999 provided an opportunity to investigate the impact of such an extreme event in terms of damage and mortality of adult trees in floodplains. Such data is highly valuable for determining the potential impact of climate change on the zonation of tree species along rivers. We analysed an extensive dataset of the damage and mortality suffered by groups of adult trees of the following species as a consequence of this flood: the hardwoods Acer campestre L., Acer platanoides L., Acer pseudoplatanus L., Alnus glutinosa (L.) Gaertn., Carpinus betulus L., Fagus sylvatica L., Fraxinus excelsior L., Juglans nigra L., Prunus avium (L.) L., Quercus robur L., Tilia cordata Mill., Ulmus laevis Pall. and Ulmus minor Miller, and the softwoods Salix spp. L. and Populus spp. L.A logistic survivorship curve revealed that mortality of A. platanoides, A. pseudoplatanus and T. cordata increased significantly with increasing duration of flooding; C. betulus and F. excelsior showed a significant increase of damage and mortality with increasing flooding depth. There was no mortality of Salix spp. and Populus spp. in either the flooded or unflooded areas. No statistically significant relationships were found for the other tree species. Multivariate analysis revealed that flooding duration, flooding depth and flooding velocity explain 19%, 11% and 8%, respectively, of the variation in damage and mortality of trees.The survivorship curves of adult trees obtained in this study were combined with similar curves of saplings based on an earlier study and applied in an individual-tree, process-based simulation model. The simulated effects of flooding on an initial random distribution of trees species on a hypothetical floodplain resulted in a realistic zonation of tree species along the river. When extreme events were simulated, the zonation shifted upward. This demonstrates the model's usefulness in assessment and planning studies of the impacts of climate change on tree species composition in river floodplains in north-west Europe.  相似文献   

9.
Food range and economic importance of the predator mite, Agistemus exsertus Gonz. (Acari, Prostigmata) The predator miteAgistemus excertus fed on eggs ofTetranychus arabicus, crawlers of the scale insectChrysomphalus ficus, eggs of bothLipidosaphes baledi, andL. beckii, while it did not feed on eggs ofC. ficus and crawlers ofL. beckii. The predator developed and reproduced on all the four former prey types but at different rates. Eggs ofT. arabicus were the best food for quiker development, longer longevity and higher rate of reproductivity. These were followed by eggs ofL. baledi, crawlers ofC. ficus, and eggs ofL.beckii.  相似文献   

10.
Species composition of galls on the leaves of Acer pseudoplatanus L. was analysed in 2002 in three localities: the Wolski Forest, near an urban agglomeration of Kraków, the Ojców National Park and the Andrychów Forest District. A total of 12,013 galls were found. The galls were caused by six insect or mite species. The species composition of the galls was identical in the three localities. Artacris cephaloneus (Nalepa) was the most abundant species. The index of occurrence frequency and Agrells index of species co-occurrence were calculated. The index of occurrence frequency (F) value was highest in the case of A. cephaloneus (1.277) and the lowest value, i.e. 0.00005—both from the Wolski Forest. The highest value for Agrells index of species co-occurrence, i.e. 0.900, was found in the case of Eriophyes pseudoplatani Corti and Drisina glutinosa Giard (Ojców National Park), and the lowest,0.050, for D. glutinosa and Coptophylla gymnaspis (Nalepa) (Wolski Forest; Andrychów FD) and for D. glutinosa and Dasineura irregularis (Bremi) (Andrychów FD).  相似文献   

11.
Estimation of shrub biomass can provide more accurate estimates of forest biomass and carbon sequestration. We developed species-specific biomass regression models for four common shrub species, Chinese loropetal (Loropetalum chinense), white oak (Quercus fabri), chastetree (Vitex negundo var. cannabifolia), and Gardenia (Gardenia jasminoides), in southeast China. The objective of this study was to derive appropriate regression equations for estimation of shrub biomass. The results showed that the power model and the quadratic model are the most appropriate forms of equation. CA (canopy area, m2) as the sole independent variable was a good predictor of leaf biomass. D 2 H, where D is the basal diameter (cm) and H is the shrub height (cm), is a good predictor of branch and root biomass, except for V. negundo var. cannabifolia and the root biomass of L. chinense. For total biomass, D 2 is the best variable for estimation of L. chinense and G. jasminoides, and D 2 H is the best variable for estimation of Q. fabri and V. negundo var. cannabifolia. Although variables D 2, D 2 H, and H are the preferred predictors for biomass estimation, CV (canopy projected volume, m3) could be used alone to predict branch, root, and total biomass in shrub species with acceptable accuracy and precision.  相似文献   

12.
With an increasing demand of sustainable raw materials for bioenergy use, coppicing as management approach to increase the biomass production of forests is becoming of greater importance. This study describes the parameterization of biomass equations for six tree species traditionally used in coppices forests, namely sycamore maple (Acer pseudoplatanus L.), field maple (Acer campestre L.), European ash (Fraxinus excelsior L.), European hornbeam (Carpinus betulus L.), downy birch (Betula pubescens Ehrh.), and common hazel (Corylus avellana L.) growing in coppice-with-standard systems in Lower Saxony, Germany. The parameterization was based on measurements of over 950 trees sampled from two forest sites. The sampled trees were felled and separated into three biomass compartments (stem, coarse branches, and fine brushwood) and weighed on site. The dry weight of sub samples from each compartment was measured. Equations were derived for total aboveground biomass, stem biomass, and crown biomass using regression analyses. We either used diameter at breast height as single independent explanatory variable or in combination with tree height. Biomass production of stump sprouts and generatively grown stems was compared for ash and sycamore maple. In the same age classes, it was found that ash stump sprouts had a slightly higher production than seed-grown stems. For sycamore maple, no difference was detected.  相似文献   

13.
The influence of tree species and soil properties on leaf litterfall concentrations and fluxes of elements were studied in three mixed deciduous forest stands. Leaf litterfall fluxes of sixteen elements were measured during autumn defoliation in 100 to 150 yr old individuals of Fagus sylvatica L., Quercus robur L., Carpinus betulus L., Tilia cordata Mill, and Acer platanoides L. Compared to throughfall and precipitation, leaf litterfall dominated the flux of P, Ca, Mn, N and Mg (in decreasing order) to the soil below the tree canopies. For K and especially S and Na, however, the importance of leaf litterfall input to the total fluxes was small. Fluxes and especially concentrations of Ca, Mg, K, P and partly N were positively related to base saturation of the soil, while Mn was negatively related due to a higher mobilization rate and plant uptake of this element on acid soils. Litterfall fluxes for C. betulus were strongly positively influenced by base saturation and fluxes were usually higher than for F. sylvatica and Q. robur at the richest site. Quercus robur had often the lowest fluxes, especially of Ca and Mg. Tilia cordata had the highest leaf litter concentrations in twelve of the sixteen elements, and the highest fluxes particularly of N and K. Acer platanoides had the highest or among the highest concentrations and fluxes of Ca, Zn and Mn. The concentration of Al in C. betulus leaf litterfall, was about five times higher than in all other tree species at all sites.  相似文献   

14.
Analytical studies were conducted of the species composition of galls occurring on the leaves ofAcer pseudoplatanus L. in the Ojców National Park in the years 1994–1995. The species composition of galls was similar in both years. The most numerous species wereAceria pseudoplatani (Corti) andDasineura vitrina (Kieff.) in 1995. Index of occurrence frequency and Agrell's index of species co-existence have been calculated.  相似文献   

15.
Possible reutilization of fresh and aged culture wastes of mushrooms for cultivatingLyophyllum decastes was investigated, although bark compost has commonly been used as a substrate for cultivating this fungus. The culture wastes studied were obtained after harvestingPleurotus ostreatus andPholiota nameko mushrooms. Mycelia ofL. decastes grew in the media containing both the fresh culture waste ofP. nameko and bark compost. However, it did not grow in the medium containing only the fresh culture waste ofP. nameko or in any media containing the fresh culture waste ofP. ostreatus. The mycelial growth inhibition in the fresh culture wastes ofP. ostreatus might be caused by the water-soluble inhibitors present. Mycelia ofL. decastes grew in all the media with aged culture wastes of bothP. ostreatus andP. nameko, which had been left outdoors for 6 months, regardless of whether bark compost was mixed. Fruit bodies were produced on all the tested media with aged culture wastes of both mushrooms, which had been left outdoors for a year. The aged culture waste ofP. nameko gave greater yields than the bark compost. This investigation shows that the aged culture wastes ofP. ostreatus andP. nameko could be reutilized for producingL. decastes mushrooms.This study was presented in part at the 47th annual meeting of Japan Wood Research Society, Kochi, April 1997  相似文献   

16.
Summary L. cyanella L. is known to occur in Europe, Siberia, and Japan. A map showing personal records ofL. cyanella on creeping thistle(Cirsium arvense) is given in Figure 2. Our findings suggest thatL. cyanella is more common and more evenly distributed in the western parts of Europe (western France and southern England) than in central Europe (Switzerland, Germany, Austria), where only a very small proportion of the thistle stands examined yielded the beetle. There are no personal records from southern Europe. The hibernating adults ofL. cyanella appear in late April and May on the rosettes and young shoots ofC. arvense, where they start feeding and ovipositing. The larvae which are covered with their faeces feed on the lower side of the leaves ofC. arvense. Pupation takes place in the soil. In the laboratory the whole development from egg to adult lasted about 35 days. There is only one generation per annuum. All available field observations ofL. cyanella refer toC. arvense as host plant (one record fromCirsium vulgare). “Short-term feeding tests” with adults ofL. cyanella yielded feeding responses withCarduus,Cirsium spp. andSilybum. Test plants belonging to 17 other genera of the Compositae family were not accepted. As shown in Table 1 this “Carduus-Cirsium-Silybum pattern” has also been found in feeding experiments with other highly specialized thistle insects. Within its subfamily (Criocerinae)L. cyanella appears to have developed a unique host association, since to date no related species are known to feed on thistles or other Cynareae. Because of its high degree of host specifityL. cyanella may be a potential candidate insect for the biological control of creeping thistle in North America. Further feeding tests with larvae and investigations as to the reasons for the scarcity ofL. cyanella in central Europe should be made, before a definite decision about the usefulness ofL. cyanella as a biological control agent can be taken.   相似文献   

17.
Control of Lymantria dispar L. by biological agents   总被引:1,自引:0,他引:1  
The experiment on control ofLymantria dispar L by using different kinds of biological measures, including nuclear polyhedrosis virus (NPV) ofLymantria dispar L., BtMP-342, sex-attractant as well as botanical insecticide, was carried out in the forest regions of Inner Mongolia in 2003. Two concentrations (2.632×106 PIB·ml−1 and 2.632×107 PIB·ml−1) ofLymantria dispar L. NPV were sprayed on the 2rd-instar-larvae ofL. dispar and 70% and 77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instar larvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific Forestry Research Center also showed a good result in trappingL. dispar adults. The self-produced botanical insecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains, China, exhibited a good control result in controlling the larvae ofL. dispar, and 82% mortality was observed when spraying primary liquid of the botanical insecticide on the 3rd–5th-instar-larvae in lab. Foundation item: This paper was supported by Natural Science Foundation of Heilongjiang Province (C0235) and Youth Foundation of Harbin City (0061218024). Biography: ZHANG Guo-cai (1964), male, Ph. Doctor Candidate, associate professor in School of Forestry, Northeast Forestry University, Harbin 150040, P. R. China. Responsible editor: Song Funan  相似文献   

18.
Fifteen eriophyid mite species are the most abundant species in the Czech Republic from which four, viz.Eriophyes fraxinivorus onFraxinus excelsior, E. platanoideus onAcer platanoides, Phytoptus pyri onPyrus communis andStenacis triradiatus on various species ofSalix injure their host plants and are evaluated as pests. The weight of the leaves attacked by eriophyid mites increase with increasing number of galls pro leaf but the surface of attacked leaves decrease with increasing attack. Harmfulness of eriophyid mites manifests by reducing of assimilation processes, retardation of growth, precocious drying and fall-off of attacked leaves. Heavily attacked young shrubs and trees may dry and decease.With one figure and 2 tables  相似文献   

19.
The parasitoid complex of Saperda populnea (L.) (Col., Cerambycidae) was studied during the period 2002–2003 at different sites in Bulgaria. Galls containing cerambycid larvae were collected on branches of aspen (Populus tremula L.), goat willow (Salix caprea L.) and hybrid poplars and were studied under laboratory conditions. As a result, four new species for the parasitoid complex of S. populnea in Bulgaria were recorded: Dolichomitus tuberculatus (Geoffroy), Xylophrurus lancifer (Gravenhorst), Gelis ornatulus (Thomson) (Hym., Ichneumonidae) and Dendrocerus serricornis (Boheman) (Hym., Megaspilidae). D. serricornis and G. ornatulus are new species for Bulgarian fauna. D. tuberculatus and X. lancifer were found as primary parasitoids, and G. ornatulus and D. serricornis as hyperparasitoids. The primary parasitoids developed solitarily in the host larvae. D. serricornis was reared gregariously from a puparium of Billaea irrorata (Meig.) (Dipt., Tachinidae). The host of G. ornatulus was not identified, but the hyperparasitid could be connected with Iphiaulax impostor (Scop.) (Hym., Braconidae). The mortality of S. populnea caused by the parasitoids was 2.0–6.3%.  相似文献   

20.
An overview of knowledge about the horse chestnut minerCameraria abridella Desch. & Dem. (Lep., Gracillariidae), a pest developing in leaf mines ofAesculus bippocastanum, spread gradually from the Ohrid-Lake (Macedonia) through Bosnia, Serbia and Croatia up to the central Europe (fig.). At present (1999) it occurs in northern Italy, Switzerland, Hungary, Czech and Slovak Republics, Austria, southern and central Germany and in southern Poland. Usually three, but up to five generations develop a year in central-European conditions.C. obridella develops also in leaf mines onAcer pseudoplatanus andA. platanoides. The parasitation is 1–8% and seems not to increase. Heavily attacked trees do not die; only rarely the dying of heavily damaged trees have been observed. Several insecticides may be used to control of this pest. The most successful was the growth-regulator Dimilin with active substance of Diflubenzurol. In the future it will be possible to control populations ofCameraria obridella by pheromones. The future development of this pest and its control is discussed.   相似文献   

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