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《经济林研究》2021,(2)
【目的】解决传统沙棘硬枝扦插和嫩枝扦插中插穗取材有限、插穗获取费时费工等问题,实现优良沙棘单株短时间内的大量扩繁,降低生产成本,为沙棘扦插育苗生产提供新的思路与方法。【方法】以2～8 cm非木质化的沙棘嫩芽作为插穗进行扦插试验,研究温度、湿度、光照强度、扦插基质、采穗日期等因素对沙棘嫩芽插穗生根的影响,同时使用不同种类、配比及质量浓度的外源激素对嫩芽插穗进行处理,筛选促进沙棘嫩芽插穗生根的最佳激素处理。【结果】促进沙棘嫩芽插穗生根的最佳环境条件为温度25℃、湿度85%、光照强度5 000 lx。环境因素对沙棘嫩芽插穗生根率的影响由强到弱依次为湿度、温度、光照。最佳采穗日期为6月20日—7月20日。外源激素种类、配比及质量浓度对沙棘嫩芽插穗的生根效果有重要影响。其中,IBA+NAA(10︰1)处理中,质量浓度为200 mg/L时,插穗生根效果最佳,生根率达96.7%以上,不定根平均长度达5.8 cm,不定根平均数量为23。以泥炭土+珍珠岩(体积比3︰1)作为扦插基质,插穗生根率较高,且后期根系生长速度快。【结论】6月20日—7月20日采集沙棘嫩芽作为插穗,使用200 mg/L的IBA+NAA(10︰1)溶液处理插穗,在温度25℃、湿度85%、光照强度5 000 lx的环境条件下进行扦插,可以实现优良沙棘单株短时间内的大量扩繁。 相似文献
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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
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通过对银杏不同插穗枝条、插穗愈合生根条件、插穗剪口形状、树龄、生根粉浓度进行对比试验,结果表明:插穗剪口为斜剪口,室内相对湿度85%~95%,温度22~28℃,基质含水率35%~55%的环境是保障银杏插穗正常愈合生根的最佳条件;银杏各类枝条插穗在生根粉溶液中浸泡的时间长短对插穗愈合生根无明显影响;生根粉的浓度为100 mg.L-1时插穗生根率最高。 相似文献
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利用不同节数(芽数)嫩枝插穗进行扦插试验,结果表明不同节数嫩枝插穗扦插皆可生根,但生根率差异较大;1～2节(1～2芽)插穗生根率低,3节(3芽)以上生根率较高,生根率随节数(芽数)的增加而提高. 相似文献
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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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《中南林业科技大学学报(自然科学版)》2017,(8)
以南京椴嫩枝为研究材料,通过设置不同IBA粉剂处理浓度、穗条制备保留叶片数量、制备穗条的枝条粗度等,研究穗条制备及处理对南京椴嫩枝扦插生根的影响。研究结果表明:使用IBA粉剂处理有助于插穗生根,处理浓度以1 000~1 500 mg·L~(-1)为宜,可兼顾扦插生根率与生根质量;嫩枝插穗适度保留叶片有助于生根,保留一片完整叶片效果最佳,生根率可达80%,且所生根系质量较优,除腐烂插穗外其余插穗全部生根;插穗粗度对插穗生根效果存在影响,幼嫩细枝扦插生根率较低且所生根系质量不高,插穗粗度应不低于0.55 cm;南京椴扦插生根不属于愈伤组织生根型,其多由插穗下切口处及切口上部皮部生根;水分控制对于南京椴嫩枝扦插至关重要,选用透水效果较好的珍珠岩、及时拣除掉落叶片、增加自动喷雾频次、降低喷雾时间等措施将有利于插穗生根。南京椴嫩枝扦插以选用粗度0.55 cm以上半木质化枝条制备插穗为宜,插穗长10~15cm,上切口平截,下切口单面斜切,保留一片叶片,扦插前插穗基部蘸取1 000~1 500 mg·L~(-1) IBA粉剂进行促根。 相似文献
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在丹东地区丘陵山地开展了银杏扦插繁殖试验,对插穗截取部位、萘乙酸生根剂不同浓度和插穗长度对扦插成活率和生根率的影响进行了分析。结果显示:银杏1年生枝条中部生根率较高,生根率可达84.4%;NAA的浓度影响生根率,其中400μg·kg~(-1)成活率最高;8~12cm长的插穗,生根率均达到90.83%以上。 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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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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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
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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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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