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2013年6月在福建邵武市苗圃对桂花进行了当年生半木质化嫩枝扦插繁殖试验。采用不同生根促进剂、不同浓度,以及不同扦插基质处理。6个月后结果表明:桂花的嫩枝扦插生根率有显著差异,生根数量及根长等生根性状未达显著差异水平;桂花嫩枝扦插较佳的处理组合是:ABT3号生根剂,质量浓度为250 mg·L-1,生根率达90.0%;桂花在不同扦插基质条件下,生根率以2号基质(黄心土70%+河沙30%(体积比))较好。 相似文献
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曼地亚红豆杉扦插繁殖研究初探 总被引：4，自引：0，他引：4
连续3 a在福建闽清进行曼地亚红豆杉扦插繁殖试验,结果表明:用100 mg.L-1的NAA浸泡插穗6 h,生根率最高,可达92%;不同基质间生根率差异显著,混合基质(蛭石∶珍珠岩∶河沙=2∶2∶3)效果最佳,生根率达95%;不同年龄插穗扦插生根率差异显著,1年生穗条生根率最高,生长势最旺;最佳扦插时间是秋季(9月)。 相似文献
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为解决美国白蜡嫩枝扦插苗生根率低、根系不发达等技术瓶颈问题,以1年生美国白蜡嫩枝为材料,采用单因素随机区组试验设计,研究蚯蚓粪、插穗部位和扦插时间对美国白蜡扦插繁育的影响。结果表明,不同蚯蚓粪配比、插穗部位和扦插时间对美国嫩枝扦插苗生根率、生根数量、最大根长和平均根长的影响差异达到显著水平。以基质3（蚯蚓粪∶蛭石=2∶1）为扦插基质插穗生根率最高,为90.24%;中部位置插穗生根率最优,为89.23%;8月份扦插的效果最好,生根率为91.56%。综上,以基质3为扦插基质,采用美国白蜡1年生枝条的中部位置为插穗,扦插时间为8月份上旬,扦插生根效果最佳,当年苗高达到95 cm左右。 相似文献
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通过试验研究了卷斗青冈母树树龄(A)、NAA使用浓度(B)及插穗长度(C)对卷斗青冈扦插生根率的影响;比较了不同插穗下切口型(D)对卷斗青冈扦插生根率的影响;研究了不同基质配方网袋容器(E)对卷斗青冈扦插苗移栽成活率的影响。结果表明:母树树龄、NAA使用浓度及插穗长度这3个因素对卷斗青冈扦插生根率影响的主次关系是ABC,母树树龄5a(A1)+NAA使用浓度为800mg·L-1(B2)+插穗长度13cm(C2)组合最好,其生根率最高;不同插穗下切口型的扦插试验中,以平切面(D1)的生根率最高;将已诱导生根的卷斗青冈扦插苗移栽至6种配方的轻基质网袋容器中,以泥炭∶椰粉∶珍珠岩=3∶2∶1(E6)的配方的生长情况最优。 相似文献
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在节能二代温室内用穴盘进行栓翅卫矛的嫩枝扦插育苗试验。结果表明,在7年生优良母树上,采集母树中上部1年生嫩枝,在6月底7月初用1 000 mg/L的IBA+NAA生根剂溶液速蘸10~15 s后,按蛭石∶珍珠岩=1.5∶1的比例作基质进行扦插,其生根时间早,成活率最高,生根率达到90%以上。 相似文献
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互叶白千层扦插育苗技术初探 总被引：6，自引：1，他引：5
以互叶白千层当年生的嫩枝为试验材料,采用L9(34)正交试验方案,研究不同生根促进剂、不同浓度以及不同基质对互叶白千层扦插生根的影响,筛选各因素水平的最佳组合。试验结果表明:生根促进剂的种类及其浓度对扦插生根影响显著;ABT/NAA混合促进剂,浓度为1 000 mg.kg-1,基质采用珍珠岩和泥土1∶2组合,是互叶白千层扦插最佳的因素水平组合。其生根率可达78%,生根数可达4.02条,最长生根长度为3.48 cm。 相似文献
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紫椴嫩枝扦插繁殖技术研究 总被引：3，自引：0，他引：3
为了筛选能提高紫椴生根率的扦插繁殖技术,文中研究了植物生长调节剂的不同种类(ABT1、IBA、NAA)、浓度(50、100、200 mg L-1)、浸泡时间(1、4、8 h)、基质类型(河沙、蛭石、体积比为3∶1的泥炭与珍珠岩)、母株年龄(1、2 a)对紫椴嫩枝扦插生根质量的影响情况。结果表明:植物生长调节剂的处理效果以IBA为最好,其对紫椴嫩枝的生根率、生根数量和平均根长的影响显著;嫩枝扦插,以100 mg L-1的IBA浸泡时间8 h的处理为最优组合,其生根率为63.07%;3种不同类型扦插基质的生根效果明显不同,河沙的生根效果最好,生根率最高达到37.16%,蛭石次之,泥炭土+珍珠岩(体积比为3∶1)最差。不同母株年龄对紫椴嫩枝扦插生根的影响也不同,1年生紫椴嫩枝的生根质量比2年生嫩枝好,其生根率、生根量和平均根长均明显优于后者。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
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
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
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
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
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
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
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
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Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and
also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the
amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter
bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K
was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed
significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed
during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly
between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species
provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient
enrichment capacity and slower decomposition rates which would minimize leaching losses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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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
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Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):118-130
The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions. 相似文献
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Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
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《Wood material science & engineering》2013,8(2):76-84
Abstract Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists. 相似文献