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1.
用油松嫩枝作插穗，在粗河沙中扦插育苗，插后先形成愈合组织，后从愈合组织处生根，皮部不生根，以浓度１０００μｇ／ｇ萘乙酸处理生根率最高，为５７．７％，移栽成活率为９４．９％。 相似文献
2.
利用全光雾插技术对长白落叶松半木质化插穗扦插育苗研究表明：夏插３０ｄ后开始生根，从扦插至大部分插穗生根（７２．７％）需要７２ｄ时间。２．５ａ生插穗未经激素处理生根率达７０．８％，利用２００ｇ／ＬＩＢＡ溶液浸泡２０ｍｉｎ后，插穗生根率提高到８０％；不同采穗母株间插穗生根率变异幅度为３２％～９５．３％，差异达到极显著水平；不同年龄插穗经２００ｇ／ＬＩＢＡ溶液处理后生根率随母株年龄的增大而降低。 相似文献
3.
龙眼和荔枝为我国特产优质果品，是公认的扦插难生根成活的树种。近年来，我们通过用流水、ＡｇＮＯ３或乙醇等溶液浸泡处理先去除枝条内部抑制生根的物质，然后用ＡＢＴ１号生根粉处理枝条基部，通过认真管护，龙眼扦插愈合率达８７．６％，生根率达７８．２％，成活率达７４．５％；荔枝扦插愈合率达５６．１％，生根率达４７．６％，成活率达４６．３％。苗木移栽后生长良好 相似文献
4.
ABT生根粉在龙眼和荔枝扦插育苗中应用技术研究 总被引：3，自引：0，他引：3
龙眼和荔枝对我国持产优势果品，是公认的扦插难生根成尖的树种。近年来，我们通过用流水，ＡｇＮＯ３或乙醇等溶液浸泡处理先去除枝条内部抑制生根的物质，然后用ＡＢＴ１号生根粉处理枝条基部，通过认真管护，有扦插愈合率达８７．６％，生根率达７８．２％，成活率达７４．５％；荔枝扦插愈合率达５６．１％，生根率达４７．６％，成活率达４６．３％。苗木移栽后生长良好。 相似文献
5.
植物生长素对东北红豆杉嫩枝扦插生根的响 总被引：2，自引：0，他引：2
以ABT-1^#、2．4-D、IAA、IBA、NAA5种植物生长素处理东北红豆杉当年生半木质化嫩枝，进行扦插生根试验，结果表明：嫩枝插穗扦插40-60d后在形态下端形成愈合瘤，并逐渐长出不定根，属于愈合组织生根型；在激素配比均为100×10^-6的条件下，经2．4-D处理的插穗生根率达到68％以上，经ABT—1^#和IBA处理的达到52％以上；采自幼龄植株的嫩枝插穗生根率高于老龄植株。 相似文献
6.
西伯利亚落叶松扦插较难生根，１９９２～１９９３年在哈密林木良种基地进行了全光喷雾嫩枝扦插育苗试验。结果表明，以锯末为扦插基质，用１．５ａ生西伯利亚落叶松嫩枝扦插，平均生根率达到８０．３９％；平均生根数量５．８６条，每穗平均根长１．７８１ｃｍ。初步认为，提高西伯利亚落叶松幼龄母树嫩枝扦插生根效果的最佳组合是：锯末（基质），扦插密度２ｃｍ×４ｃｍ，生根粉（ＡＢＴ）５００μｇ／ｇ，插条长度８～１０ｃｍ。 相似文献
7.
杂种松扦插繁殖试验初报 总被引：13，自引：4，他引：9
通过近３年的杂种松扦插繁殖试验结果表明,选用黄泥心土基质、穗条采下后浸于５０ｍｇ／ｋｇ的台化牌植物生根促进剂溶液或１ｇ／ｋｇ多菌灵溶液各０．５ｈ或浸于１ｇ／ｋｇ多菌灵溶液０．５ｈ后蘸黄泥浆扦插等处理、在冬春季节光照充足的圃地、穗条长６～１４．５ｃｍ、顶端次生叶长５．５～１３ｃｍ等条件下扦插生根率高;并且在穗条、管理措施、扦插季节等条件合适的情况下,部分家系的扦插生根率较稳定,可达到７５％,最高达１００％。大规模扦插试验平均生根率达９１％。 相似文献
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9.
以柳桉带腋芽的幼嫩茎段为外植体进行组培快繁，其启动培养、增殖培养、生根培养的最佳培养基依次为MS＋6-BA2＋NAA1、改良MS＋6-BA0．2＋NAA0．2＋IBA0．8、改良MS＋NAA0．2＋IBA0．8，繁殖系数可达3以上，生根率可达85％以上；试管苗移栽前需炼苗10—15d，移栽时间选在3、4、10、11月份移栽成活率最高，可达90％以上；柳桉萌发力强，试管苗移栽成活后长到一定高度经过采穗可促使腋芽不断；蒡发，生产上可利用此原理建立田间采穗圃，1株试管苗6个月内可供采穗10—12根；试管苗移栽前必须经过一个炼苗阶段，炼苟时间为10—15d，移栽成活率可达90％以上；气温与柳桉扦稳的愈合、生根关系十分密切，在气温18—25℃时扦插，有利于插穗愈合生根；使用50mg／LGGR溶液处理插穗，可使插穗生根提早5d左右，同时可使生根率提高10％。 相似文献
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11.
《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
12.
《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
13.
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
14.
《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
15.
《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
16.
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
17.
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
18.
《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
19.
《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
20.
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