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以溪荪为试验材料,研究了消毒时间、外植体种类对溪荪组织培养的影响,筛选出了适宜的初代培养基、增殖培养基和生根培养基。试验结果表明:适宜的外植体为带芽根状茎,以1g/L的HgCl2消毒8min效果最好。适宜的初代培养基为MS+BA1.0mg/L+NAA0.2mg/L,诱导成苗率达88.57%。适宜的增殖培养基为MS+BA2.0mg/L+NAA0.2mg/L,增殖系数为4.72。适宜的生根培养基为MS+BA0.1mg/L+NAA0.5mg/L,平均每株生根数量为8.9条,平均根长为2.5cm,平均根粗为1.0mm。 相似文献
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文章以尾叶桉(Eucalypt urophylla)优良新无性系的无菌组培苗为材料,MS培养基为基本培养基,研究6-BA、NAA不同质量浓度配比对尾叶桉无菌幼苗丛芽增殖率,以及生根粉种类、质量浓度、不同IBA和NAA配比对不同尾叶桉无性系生根率的影响.试验结果表明,当6-BA质量浓度为0.01 mg/L,丛芽增殖率在NAA质量浓度为0.01、0.1 mg/L时递增;而NAA质量浓度为1、5 mg/L时,则有利于生根;筛选出适宜尾叶桉优良无性系ZQUA10的增殖培养基为MS+0.01 mg/L 6-BA+0.01 mg/L NAA+30 g/L蔗糖+6 g/L卡拉胶,增殖系数达到4.7;筛选出适宜尾叶桉优良无性系ZQUA13的生根培养基为1/2MS+0.5 mg/L ABT1+30 g/L蔗糖+6 g/L卡拉胶,生根率达到57.5%;筛选出适宜尾叶桉优良无性系ZQUB58的生根培养基为1/2MS+1 mg/L IBA+0.5 mg/L NAA+30 g/L蔗糖+6 g/L卡拉胶,生根率达到100%. 相似文献
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对大花蕙兰的无菌播种及组培快繁技术进行了相关研究。结果表明:大花蕙兰无菌播种采用0.1%升汞溶液灭菌10 min能取得较好的效果;改良MS+6-BA1.0 mg/L+NAA 0.5 mg/L培养基对假鳞茎诱导原球茎效果较好,其原球茎诱导率可达86%;原球茎增殖的最佳培养基为改良MS+NAA 0.5 mg/L,此配方对大花蕙兰的壮苗生根同样合适;采用固、液培养基交替培养(振荡转数100～110 r/min)能有效地促进原球茎增殖;移栽基质配比为腐殖土∶棉籽壳=1∶1时,移栽苗成活率可达95%。 相似文献
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以不同浓度梯度无机盐离子与蔗糖对大花蕙兰‘天使’与蕙兰‘绿蕙’杂交后代组培苗生根进行研究。试验结果表明:无机盐离子与蔗糖浓度杂交兰生根影响极其显著。最适无机盐浓度为1/4MS,60 d后组培苗生根率达到100%,平均生根数最多为2.4条,平均根长最长为1.79 cm;最适蔗糖浓度为30 g/L,根生长状况最佳,平均生根数最多为3.43条,平均根长最长为1.34 cm。杂交兰最适生根培养基为1/4MS+NAA0.2 mg/L+琼脂8.0 g/L+蔗糖30 g/L+香蕉泥150g/L。杂交兰组培苗移栽试验表明:对根部进行断根处理,可刺激新根的生成,提高幼苗成活率,与未进行断根处理的相比,苗的长势也明显见好。 相似文献
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《热带农业科技》2021,(4)
以‘燕窝果’幼嫩茎段为外植体,通过筛选外植体消毒方法,刺座芽增殖和壮苗生根等适宜培养基,建立离体快繁技术体系,旨在为燕窝果的工厂化育苗提供技术支撑。结果表明,最适合外植体消毒的方法为75%酒精消毒10 s,5%双氧水3 min,0.1%升汞3 min,污染率为5%,成活率达94.7%;适宜刺座芽增殖的培养基为MS+0.5 mg/L NAA+1.0mg/L TDZ,增殖系数为4.53,平均芽高为3.23 cm;适合不定芽壮苗生根的培养基为1/2MS+0.5 mg/L IBA+1.0 mg/L NAA+0.1 g/L碳粉,平均生根数达6.18,且不定芽与根系长势良好。 相似文献
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外源激素对大花蕙兰组织培养的影响 总被引：1，自引：0，他引：1
以茎尖为外殖体进行大花蕙兰组织培养,研究表明：大花蕙兰茎尖在MS＋6-BA1.5mg/L＋NAA0.1mg/L培养基上培养25d后,茎尖分化形成原球茎;原球茎在1/2MS＋6-BA2.0mg/L＋NAA0.1～0.2mg/L培养基上增殖速度最快,增殖系数可达7.62;原球茎在1/2MS＋NAA0.2mg/L培养基上分化最好,分化的大花蕙兰幼苗在1/2MS培养基上生根效果好。 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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《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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《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
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Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
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A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献