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红松SSR-PCR反应体系的建立与优化 总被引：3，自引：2，他引：1
为了建立红松SSR-PCR最佳反应体系,以CTAB法提取的红松针叶DNA为模板,应用单因子试验及L16(45)正交试验系统分析了DNA模板浓度、Mg2+浓度、dNTPs浓度、引物浓度、Taq酶浓度等对SSR-PCR扩增结果的影响,并对延伸时间、热循环参数进行了探讨,建立了稳定的、可重复的红松SSR-PCR最佳反应体系及PCR扩增参数。结果表明,PCR的最佳反应体系为:10μL体系中,1×PCRbuffer1μL、DNA模板50～120ng,Mg2+3mmol/L,dNTP0.4mmol/L,引物0.5μmol/L,Taq酶0.75U。利用该体系筛选出扩增条带清晰、多态性丰富的SSR引物13对。在此反应体系下,所扩增谱带清晰、稳定、多态性高。 相似文献
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为建立一个具有良好稳定性和可重复性的野生小果油茶ISSR-PCR反应体系,以提取的野生小果油茶总DNA为供试材料,利用单因素试验,正交试验设计L16(45)和方差分析对DNA模板的量,引物浓度,dNTPs浓度,Mg2+浓度,Taq DNA聚合酶的量5个影响ISSR-PCR反应体系的因素进行优化研究。确定野生小果油茶ISSRPCR最优反应体系为:在20μL的反应体系中,DNA模板为30 ng,引物浓度为0.7μmol/L,dNTPs浓度为0.25mmol/L,Mg2+浓度为2.0 mmol/L,Taq DNA聚合酶的量为1.75 U。方差分析结果表明,5个因素对体系的影响均未达到显著水平,其中引物浓度对反应体系影响最大。应用建立的体系对5份野生小果油茶样品进行扩增,证明了该体系具有稳定性和可重复性。 相似文献
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以川山茶品种"茶睡莲"为试验材料,以改良CTAB法提取高质量DNA,采用正交设计L16(45),探讨了Mg~(2+)、dNTPs、引物、TaqDNA聚合酶和模板DNA浓度对川山茶ISSR-PCR和SSR-PCR反应体系的影响。建立了相关优化体系:20μL的ISSR-PCR扩增体系中含20 ng模板DNA,2μL10×Buffer,2 mmol/L Mg~(2+),0.15 mmol/L dNTPs,0.6μmol/L引物和1 U TaqDNA聚合酶,扩增退火温度为55℃,35个循环;20μL的SSR-PCR扩增体系中含50 ng模板DNA,2.5 mmol/L Mg~(2+),0.05 mmol/L dNTPs,0.2μmol/L引物和0.5 U TaqDNA聚合酶,最佳退火温度为52℃,最佳循环数为38。应用该优化体系,分别用27个川山茶品种DNA进行了ISSR-PCR扩增和SSR-PCR扩增,结果显示,建立的优化体系具有较高稳定性。 相似文献
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《中南林业科技大学学报(自然科学版)》2019,(8)
以云南金花茶为试验材料,利用试剂盒法、SDS法及CTAB法3种方法提取其DNA,并对3种方法的提取结果进行比较;经初筛合成云南金花茶EST-SSR引物,并对影响SSR-PCR体系的Mg~(2+)、Taq DNA聚合酶、dNTP、引物及模板DNA这5个因素进行L_(16)(45~)正交实验,以期建立较为稳定的云南金花茶SSR-PCR体系。试验结果表明:试剂盒法提取得到的云南金花茶DNA质量最好且符合SSR分子标记试验。各因素对PCR扩增效果的影响程度为:Mg2+引物 Taq DNA聚合酶 dNTP模板DNA。试验最终确定的金花茶SSR-PCR最佳反应体系(20μL)为:2.0μL Taq Buffer、1.5μL Mg2+(25 mmol/L)、0.3μL dNTP(10 mmol/L)、0.2μL Taq DNA聚合酶(5 U/μL)、前后引物各0.4μL(10μmol/L)、0.5μL模板DNA(50 ng/μL)、14.7μL ddH_2O。建立和优化云南金花茶SSR反应体系,可为云南金花茶不同种群的遗传变异研究提供基础。 相似文献
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山茱萸叶片DNA提取方法及ISSR反应体系构建 总被引：1，自引：0，他引：1
山茱萸成熟叶片中多糖及多酚类物质含量较高,传统CTAB法提取其叶片DNA效果较差,该研究在传统的CTAB提取法的基础上进行了改良,经DNA原液电泳检测及PCR产物的电泳检测表明,该法适用于提取硅胶快速干燥保存的山茱萸叶片的DNA。在此基础上,对山茱萸ISSR反应体系中的退火温度、引物浓度及模板用量进行了筛选,结果表明,在25μL的反应体系中,引物UBC847的最佳退火温度为55.2℃,引物最佳浓度为0.8μmol/L,模板最佳用量为70 ng,初步构建了山茱萸ISSR反应体系。 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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《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
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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