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1.
以刨花润楠(Machilus pauhoi)1.5 a生小苗幼嫩叶片为试材,对影响刨花润楠SRAP-PCR扩增的模板DNA量、引物、dNTP和Mg2+体积摩尔浓度、Taq DNA聚合酶、退火温度6个主要因素进行优化.结果表明,SRAP-PCR的最佳反应体系为:25μL的SRAP-PCR反应体系中,2.5μL 10×PCR buffer、模板DNA量60 ng、Mg2+2.0 mmol/L、dNTP 0.225 mmol/L、引物0.3μmol/L和Taq DNA聚合酶1.25 U.对优化的反应体系和扩增程序的验证结果表明,优化的刨花润楠SRAP-PCR反应体系和扩增程序是稳定可行的. 相似文献
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为建立国槐(Sophora japonica)最佳SRAP-PCR反应体系,采用正交试验设计L16(45)对影响PCR体系的5个因素(模板浓度、引物浓度、Mg2+浓度、Taq聚合酶和d NTP用量)4个水平进行了优化,确定了国槐的最优SRAP-PCR反应体系:Taq聚合酶1.5 U,d NTPs 0.30 mmol/L,模板DNA 90 ng,Mg2+2.0 mmol/L,引物0.3μmol/L,dd H2O补至20μL。各因素对PCR反应的影响从大到小依次为:Taq聚合酶d NTPs模板DNAMg2+引物。基于最佳SRAP体系,采用4个品种对120对引物进行筛选,共获得12对多态性好的引物组合。随机抽取两对引物基于毛细管电泳技术对此体系进行稳定性检验,扩增条带清晰、稳定、多态性高。该体系的建立以及筛选的引物组合为为进一步利用SRAP技术对国槐的遗传多样性、品种鉴定等方面的研究奠定基础。 相似文献
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为确立按树SRAP-PCR反应体系,并对桉树品种进行遗传多样性分析,以巨尾桉GL -9号嫩叶提取的DNA为模板,进行Mg2+、dNTP、引物和Taq DNA聚合酶4个因素3个水平L9(34)正交试验,并比较了不同浓度模板DNA对PCR扩增效果的影响.结果显示:桉树的SRAP-PCR最佳反应体系为Mg2+2.5 mmol/L、dNTP 0.20mmol/L、引物0.4μ mol/L、Taq DNA聚合酶1.5U,DNA模板最佳浓度为10ng.利用最佳反应体系对桉树品种进行引物组合多态性筛选,从40个引物组合中筛选出多态性引物组合17个.挑选12个多态较高的引物组合对11个按树品种进行遗传多样性分析,通过PCR扩增,得到109个谱带.其中多态性条带95条,平均每个引物组合产生7.92个多态性条带,显示了相对较高的多态性.表明SRAP标记可应用于按树分子生物学研究. 相似文献
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《绿色科技》2017,(21)
以构建珍稀物种硬叶兜兰SSR-PCR反应体系,采取正交设计试验对硬叶兜兰SSR体系组分中的Mg2+、基因组DNA、DNA Taq聚合酶、dNTPs、引物5个因素在4个不同程度上进行了组合试验,之后对反应体系中该引物的退火温度在梯度PCR仪上筛选,并进行了最优体系的验证。试验结果显示:体积为10μL的PCR管中最优组合为:模板DNA 20ng,Mg2+3.0mmol/L,dNTPs 0.3mmol/L,引物0.8μmol/L,Taq酶0.8U,10×buffer(Mg2+Free)1μL,引物PR710的退火温度为59.6℃,说明该体系具有较好的实用性。 相似文献
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以广西南宁产的金樱子叶片为材料,采用L16(45)正交试验设计,对SRAP-PCR反应体系中的Mg2+、dNTPs、TaqDNA聚合酶、引物和模板DNA用量5因素进行了优化。结果表明:适用于金樱子SRAP-PCR的最佳反应体系为:反应总体积10μL,包含2.0 mmol/L Mg2+、0.4 mmol/L dNTPs、0.5 UTaqDNA聚合酶、3μmol/L引物、25ng DNA及10×PCR Buffer;各因素对PCR反应影响由大到小依次为:Mg2+、DNA、dNTPs、引物、TaqDNA聚合酶。用7份不同来源的金樱子材料对优化的SRAP-PCR反应体系进行验证,均获得了条带清晰、多态性丰富的扩增图谱,证实了该体系的稳定可靠。 相似文献
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利用正交试验L16(45),结合单因素试验对厚朴相关序列扩增多态性(Sequence-related amplified polymorphism,SRAP)标记反应体系的5个因素(Mg2+,dNTPs,引物,Taq酶和模板DNA)进行优化试验,结果表明:各因素水平变化对PCR反应的影响从大到小依次为:dNTPsTaq酶模板DNAMg2+引物;筛选出各反应因素的最佳水平,建立厚朴SRAP-PCR反应的最佳体系(25μL)为:Taq酶1.5 U,Mg2+1.8 mmol.L-1,模板DNA100 ng,dNTP 0.24 mmol.L-1,引物0.40μL。试验表明,该体系重复性好、稳定性强。 相似文献
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通过单因素试验,对杂种松SRAP-PCR反应体系的各主要影响因子（Mg^2＋浓度、dNTP浓度、引物浓度以及Taq DNA聚合酶用量）进行了优化筛选,最终得出杂种松SRAP-PCR反应的最佳体系为：25μL体系中含有Mg^2＋2.0 mmol/L、dNTPs 0.25 mmol/L、Taq酶1.0 U,引物0.4μmol/L,模板DNA 30-50 ng以及1%体积的DMSO。采用该优化体系,对两种杂种松（火加松、湿加松）基因组DNA进行SRAP扩增,表明大部分引物对扩增出来的带清晰可辨、背景较少,完全满足分子标记的要求,为杂种松SRAP标记的相关研究奠定了基础。 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(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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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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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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《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