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为研究植物生长调节剂对幼龄檀香生长及心材形成的影响,以6年生幼龄檀香(Santalum album)为试验材料,采用树体注入的方法,比较研究3种浓度(2g/L、4g/L、6g/L)植物生长调节剂乙烯利(ETH)、茉莉酸(JA)和甲基紫精(MV)对其生长和心材形成的影响。结果表明,试验1年后,不同浓度、不同生长调节剂对6年生檀香的树高、胸径生长与CK组差异不大;但能促进檀香形成深褐色的心材。以浓度2 g/L、6 g/L乙烯利和甲基紫精处理最佳;心材直径2~3 cm,茉莉酸处理不利于心材形成。研究结果初步表明檀香不仅能在热带地区三亚生长,注射生长调节剂也能促成心材的形成。 相似文献
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为了解檀香(Santalum album L.)与不同植物的寄生关系,选取6种植物与檀香幼苗一起种植,观察这些寄主植物对檀香幼苗生长的影响情况。结果表明,檀香幼苗的吸器大小、数量在不同寄主之间存在很大差异,不同寄主对檀香的生长情况也有显著差异。整体上看,假蒿(Kuhnia rosmarnifolia Vent.)对檀香的生长表现最佳,确定为最优寄主;其次为柱花草(Stylosanthes nensias sw.)、山毛豆(Tephrosia candida)、洋金凤(Caesalpinia pulcherrima)、降香黄檀(Dalbergia odoriferan),白木香(Aquilaria sinensis(Lour.)Gilg)表现较差。 相似文献
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于2020～2022年对肇庆地区檀香(Santalum album)主要病虫害种类和危害进行了调查和鉴定,结果表明：檀香病虫害种类有13种,其中病害3种,虫害10种,其中报喜斑粉蝶(Delias aglaia)为危害檀香的主要害虫,并根据其发生危害规律,分析了报喜斑粉蝶的各个虫态;进而进行了不同农药对幼虫的室内毒理实验,筛选出最佳药剂,为进一步防治檀香害虫提供技术参考。最后,在生物防治、化学防治、物理防治、林业技术措施等4个方面进行了探讨,并提出了防治建议。 相似文献
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单因素实验设计在缓冲包装材料制备中的应用 总被引：2，自引：0，他引：2
采用单因素实验设计方案确定配方中各组分用量,在已确定木质剩余物缓冲包装材料原料配方的基础上,通过单因素实验分别单独考察不同组分用量、配比等对材料表观性能的影响,实验结果表明,木纤维含量在32-36 g,淀粉/PVA复配胶黏剂的比例在1∶1和3∶1之间,发泡剂在3-7 g,丙三醇含量在10-20 ml及滑石粉为5 g时材料的表面质量得到显著改善,分层、发泡程度及弹性均较适宜,得出木质剩余物缓冲包装材料的最佳原料配方范围为：木纤维32 g、34 g和36 g,淀粉/PVA比例1∶1、2∶1和3∶1,发泡剂3 g、5 g和7 g,丙三醇10 ml、15 ml和20 ml,滑石粉5 g,为制备具有良好的生物可降解性与环境协调性的木质剩余物纤维发泡缓冲包装材料奠定基础。 相似文献
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配方施肥对枸杞品质及产量的影响 总被引：3，自引：0，他引：3
为了解大量元素肥及微量元素肥对枸杞外观品质及产量的影响,采用正交试验设计L16(43×24),选用大量元素肥N、P、K和微量元素肥Fe、Zn、Mo、B,对3年生枸杞(宁杞1号)进行大田配方施肥试验,测定其果实大小、百粒质量及产量指标,以确定枸杞的最佳施肥配方。结果表明:不同的配方施肥组合的果实大小、百粒质量及产量均比CK增加,其最大值分别比CK增加了18.08%、38.42%、80.83%,最佳施肥水平组合为N3P2K3Fe1Zn2Mo1B1。即大量元素肥料的施肥量为:尿素217 g/株、过磷酸钙417 g/株、硫酸钾313 g/株,微量元素肥料以施入Zn肥10 g/株为好。 相似文献
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《林业实用技术》2018,(11)
以农林废弃物果树枝条木屑、棉籽壳、玉米芯及麦草为基质材料,采用混料试验设计方法,通过对不同培养料配方的菌丝生长速度、生物学效率和投入产出比的统计分析,优化农林废弃物栽培平菇的高效配方。结果表明:玉米芯34.8%、棉籽壳52.2%、麸皮10%、石灰2%、石膏1%的配方栽培平菇的平均单菇质量最大,为293.8g;麦草52.2%,棉籽壳34.8%,麸皮10%、石灰2%、石膏1%的配方栽培平菇的生物学效率最高,为148.32%;玉米芯52.2%、棉籽壳34.8%、麸皮10%、石灰2%、石膏1%和玉米芯52.2%,棉籽壳17.4%,果树枝条木屑17.4%、麸皮10%、石灰2%、石膏1%的配方栽培平菇的投产比最高,为1∶2.2。 相似文献
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花椒配方施肥试验初报 总被引：2，自引：0，他引：2
《四川林业科技》2016,(2)
在阿坝州松潘县镇坪乡镇坪村进行花椒不同配方施肥试验,研究了施肥对花椒种皮质量、含水量、出皮率的影响。结果表明:肥料的最佳配比为配方4N1P1K1,即:每株施尿素250 g,过磷酸钙750 g,硫酸钾300 g。 相似文献
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通过试验研究认为,鸡腿蘑最佳母种培养基配方为马铃薯200 g,葡萄糖10g,燕麦粉10g,琼脂20g,水1000ml,最佳出菇培养料配方为棉籽皮90％,燕麦粉8％,蔗糖1％,过磷酸钙0.5％,石膏0.5％,菌丝生长的最适温度为20～25℃,子实体发育最适温度为18～20℃,培养基的最适pH值为6.5～7.5。 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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《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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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(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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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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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