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1.
马占相思菌根调查及人工接种结果表明 :马占相思在自然界能形成外生菌根及VA菌根。在贫瘠的立地条件下 ,外生菌根的子实体多 ;在较肥沃的立地条件下 ,外生菌根的子实体少 ,优势外生菌根菌是多根硬皮马勃菌 (Sclerioermapolyrhium)。马占相思对VA菌有较强的选择性和其特定的优势VA菌根菌 ,即从马占相思根部分离的VA菌。用优势外生菌根菌及优势VA菌根菌对马占相思苗木进行接种 ,都能形成菌根 ,且都能显著地提高马占相思的生长。马占相思优势VA菌接种效果优于多根硬皮马勃菌  相似文献   

2.
西南桦对菌根的依赖性及其接种效应研究   总被引:15,自引:5,他引:15       下载免费PDF全文
为了摸清西南桦引种驯化过程中苗木菌根存在的可能性及其对菌根的依赖程度,分别对西南桦幼苗实施VA菌根和ECM菌根的接种试验。试验结果表明:西南桦幼苗对两个类型的菌根均可受感染,对菌根均有较强的依赖性,尤以对外生菌根的依赖性较强,而对VA菌根的依赖性属中等。西南桦幼苗接种外生菌根菌后180d平均苗高比对照增另了92.98 ̄106.85%,地上干质量增另206.43 ̄554.69%,地下中202.83 ̄  相似文献   

3.
泡囊丛枝状菌根对南洋杉幼苗的接种效应   总被引:4,自引:1,他引:4  
利用泡囊丛枝状菌根(VAM)菌对慢生型树种南洋杉幼苗进行人工接种,1年后的测试结果,接种VAM处理的幼苗其菌根感染率达100%,而对照株仅自然感染10.3%,接种处理幼苗的生长与对照比较,平均高增加36.5%,地径增加16.6%,平均冠幅增加36.7%,枝条数目中56.7%,接种株的生物量与对照比较,地上部分平均干重增加100.52%,地了下部分干重则增加155.76%,表明地表球囊霉9004菌株  相似文献   

4.
对厚荚相思苗期进行接种根瘤菌、菌根菌、根瘤菌+菌根菌的比较试验,结果表明:接种菌根菌的促生效果显著。幼苗高生长、地上部分干重、地下部分干重、根瘤个数、根瘤重量平均数比对照分别提高了53.36%。73.30%,89.69%,224.01%和186.96%。接种各菌种对幼苗的促生效果排序为:菌根菌+根瘤菌〉根瘤菌〉菌根菌〉对照。苗木根部菌根菌感染强度排序为:菌根菌〉菌根菌+根瘤菌〉对照。  相似文献   

5.
马占相思菌根调查及人工接种结果表明:马占相思在自然界能形成外生菌根及VA菌根。在贫瘠的立地条件下,外生菌根的子实体多;在较肥沃的立地条件下,外生菌根的子实体少,优势外生菌根菌是多根硬皮马勃菌(Sclerioerma polyrhium)。马占相思对VA菌有较强的选择性和其特定的优势VA菌根菌,即从马占思根部分离的VA菌。用优势外生菌根菌 及优势VA菌根菌对马占相思苗木进行接种,都能形成菌根,且都能显著地提高马占思的生长。马占思优势VA菌接种效果优于多种硬皮马勃菌。  相似文献   

6.
日本落叶松苗根化苗木造林效应研究   总被引:1,自引:0,他引:1  
利用接有厚环乳牛肝菌,赭丝膜菌和彩色豆马勃3种外生菌根真菌纯培养接种体的2年生日本落叶松移植苗木,进行大面积山地人工造林。结果表明,不同菌根化苗木造林成活率,树高年生长量等各项生长指标,均比对照有大幅度提高,其造林成活率为92.6% ̄98.7%,比对照提高6.2% ̄9.0%,保存率提高6.3% ̄9.9%,树高、地径年生长量分别比对照增加8.0% ̄35.3%和2.1% ̄33.5%。  相似文献   

7.
ECM和VAM菌混合接种对尾叶桉生长效应的研究   总被引:10,自引:2,他引:10       下载免费PDF全文
本文报道混合接种外生菌根真菌彩色豆马勃和VA菌根真菌苏格兰球囊霉对尾叶桉苗斯有接种效应。根系样口检查表明接种的两个菌朱均能在尾叶桉上成功合成的相应的菌根。接种后5个月试验的苗生长量和生长量的分析结果表明,接种与未接种对照差异极显著,其中,两种混合接种方式苗木干重分别比对照增加了240.3%和194.3%;苗高生长增加了73.8%和41.7%;地径增加了17.2%和19.3%。试验苗木对菌根的依赖性  相似文献   

8.
采用蜡磨菌与VA 菌根真菌分别对蓝桉和尾叶桉进行单接种或混合接种,研究结果表明,两种菌根类型的真菌均能在桉树苗木根系上成功地定殖,分别合成了外生菌根、VA 菌根和混合菌根,证实了桉树不仅是菌根营养型树种,而且能形成多种菌根类型。VA 菌根感染率在接种初期较高,但随时间的推移有降低的趋势;而外生菌根菌初期合成菌根的速度较慢,但单位长度根段内菌根根尖数目有明显增加的趋势。与单接种VA菌根真菌苗木相比,外生菌根真菌抑制了VA 菌根菌在根系上的进一步侵染,体现在较低的VA 菌根感染率;而外生菌根菌显示出了较强的竞争能力,并能在接种后9 周时开始形成子实体。在混合菌根中,外生菌根有逐步替代VA 菌根的发展趋势,两种类型的菌根真菌间存在一定的竞争性作用关系。基质磷(P)素水平对菌根的形成也有一定的影响  相似文献   

9.
菌根真菌对树苗根部病害的防治作用   总被引:1,自引:0,他引:1  
采厚环乳牛肝、血红铆钉菇、彩色豆马勃3种外生菌根菌纯培养接种物,对日本落叶松、油松播种苗进行接种试验,测定其对苗木根部病害的生物防治作用。试验表明,3种外生菌根真菌对苗木猝倒病均有的抑制作用。接种不同菌根真菌的松苗猝倒病发病率双对照降低4.0%~55.9%,苗高、地径、单株鲜重等生长指标提高2.8%~62.9%,菌根侵染率达82.0%~96.0%。  相似文献   

10.
厚荚相思等树种引种试验初报   总被引:4,自引:0,他引:4  
对厚荚相思、马占相思、肯氏相思进行引种试验,经过4年观测,厚荚相思生长最快,平均树高6.9m,年均生长1.73m,平均胸径6.1cm,年均生长1.53cm,马占相思次之。从耐干瘠、耐寒看,厚英相思和肯氏相思较好,马占相思较差。从干形和材质看,马占相思较好,厚荚相思和肯氏相思较差。从抗风性看,肯氏相思较强,厚荚相思和马占相思较差,厚荚相思是南亚热带地区台地、丘陵低山很有发展前途的工业原料林树种。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

14.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

16.
17.

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.  相似文献   

18.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

19.
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.

This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes.  相似文献   

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