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1.
以平榛花粉为试验材料,采用花粉离体培养法研究了培养基组分蔗糖、硼酸、硝酸钙不同浓度对平榛花粉萌发和花粉管生长的影响,从而找到适合平榛花粉离体萌发的最佳培养基组分。结果表明:蔗糖、硼酸、硝酸钙在一定浓度范围内可促进平榛花粉的离体萌发,超过该范围则会抑制花粉的萌发,筛选出较适宜平榛花粉离体萌发的培养基成分为蔗糖15%+硼酸0.01%+硝酸钙0.015%。  相似文献   

2.
为了探明影响暴马丁香花粉萌发的因素,筛选适宜花粉萌发的培养基,以暴马丁香新鲜花粉为试材,采用离体培养方法,通过正交设计L_(16)(4~5)研究培养基中不同浓度的蔗糖、硼酸、氯化钙及pH值4个因素对暴马丁香花粉萌发的影响。结果表明:4个因素对暴马丁香花粉萌发影响的主次关系依次为硼酸、氯化钙、蔗糖和pH值,适宜的蔗糖浓度为100~150 g/L,此时的发芽率平均为23.1%~26.6%;适宜的硼酸浓度为0.65 g/L,此时的发芽率平均为33.4%;适宜的氯化钙浓度为0.15 g/L,此时的发芽率平均为27.5%;适宜的pH值为5,此时的发芽率平均为26.8%。暴马丁香花粉萌发的最适培养基成分组合为蔗糖浓度150 g/L、硼酸浓度0.65 g/L、氯化钙浓度0.15 g/L、pH值5,在此培养基下花粉发芽率达到53.94%。  相似文献   

3.
以仙客来"大红"品种新鲜花粉为试材,用液体培养基培养花粉的方法比较了不同浓度的蔗糖、硼酸、氯化钙对花粉萌发的影响。结果表明:蔗糖和硼酸对花粉萌发的作用极显著,而氯化钙的作用没有达到显著水平。适宜的花粉培养液为:蔗糖10%+硼酸20mg/L+氯化钙30mg/L。低浓度的培养液会导致花粉内含物外流;高浓度的培养液会导致原生质体失水以致质壁分离。  相似文献   

4.
西南桦花粉离体萌发的适宜条件与萌发特征   总被引:5,自引:2,他引:5       下载免费PDF全文
应用各种浓度蔗糖、蔗糖 硼酸培养基于系列温度下开展西南桦花粉萌发对比试验,研究了蔗糖、硼酸浓度对西南桦花粉离体萌发的影响,筛选出适合西南桦花粉萌发培养基的适宜组分和适宜培养温度,并应用4个单株的花粉对其萌发特征进行了初步研究.结果表明:蔗糖基本培养基上添加硼酸能够显著促进西南桦花粉萌发;西南桦花粉离体萌发的合适培养基为15%蔗糖 200 mg·kg-1硼酸,适宜培养温度为30℃;在此条件下培养3 h后花粉萌发率基本稳定,培养7 h后花粉管长度也趋于稳定.  相似文献   

5.
以灰木莲(Manglietia glauca)的新鲜花粉为材料,研究不同浓度蔗糖、硼酸和氯化钙组合的培养基对灰木莲花粉离体萌发的影响,并用TTC染色法、I-IK染色法和无机酸法对灰木莲的花粉生活力进行了测定。结果表明:在p H值6.0时,以150 g/L蔗糖+50 mg/L硼酸+100 mg/L氯化钙+7 g/L琼脂的培养基配方最适合灰木莲花粉的培养,离体萌发率达到62.2%,花粉管生长良好;无机酸法不适宜灰木莲花粉生活力的检测;TTC染色法和I-IK染色法的测定结果与离体萌发法的结果较接近,分别为60.6%和64.1%,但I-IK染色法在观察判断上较为困难。因此,TTC染色法是快速检测灰木莲花粉生活力的最佳方法。  相似文献   

6.
以新鲜稠李花粉为试材,采用花粉离体培养法,研究蔗糖、硼酸、钙等组分对其萌发和花粉管生长的影响。结果表明:蔗糖、硼酸、钙在一定浓度范围内能够促进花粉萌发,但超过一定浓度花粉萌发率和花粉管生长都有所下降。综合分析认为蔗糖、硼酸、钙的质量分数分别为18%、0.015%、0.015%最为适宜,此时花粉萌发率最高,花粉管生长较好。  相似文献   

7.
为优化银杏花粉萌发培养基,采用离体萌发法,通过单因素试验和正交试验分析培养基中不同营养成分对银杏花粉萌发的影响。结果表明:在单因素试验中,蔗糖、硼酸和氯化钙在适宜质量浓度范围内促进花粉萌发,过高质量浓度反而不同程度地抑制花粉萌发;在正交试验中,蔗糖、硼酸和氯化钙对银杏花粉在培养基上离体萌发的影响表现极显著,适宜质量浓度分别为100 g·L-1、10 mg·L~(-1)、40 mg·L~(-1)。  相似文献   

8.
培养基成分对仁用杏花粉离体萌发的影响   总被引:1,自引:0,他引:1  
为了研究培养基成分对仁用杏花粉离体萌发的影响,以仁用杏‘优一’为试材,以蔗糖、硼酸、二水合氯化钙、赤霉素为培养基的主要成分,通过单因素和正交试验,筛选出适宜‘优一’花粉萌发的培养基成分及浓度。结果表明,4种成分在一定浓度范围内对‘优一’花粉萌发起促进作用,高质量浓度则抑制,促进‘优一’花粉萌发较适宜的浓度分别为蔗糖15%,硼酸0.003 g·L-1,二水合氯化钙0.000 2 g·L-1,赤霉素0.000 8 g·L-1;赤霉素对‘优一’花粉管伸长作用明显,其花粉管生长量、长度、节间生长显著高于其它3个处理。4种成分L25(56)的正交试验结果表明,琼脂0.1 g·L-1+蔗糖1 g·L-1+硼酸0.003 g·L-1+二水合氯化钙0.000 0 g·L-1+赤霉素0.000 6 g·L-1组合是‘优一’花粉萌发的最佳组合;‘优一’花粉在适宜萌发条件下,2~4 h是‘优一’花粉萌发的高峰期,蔗糖和硼酸是影响花粉萌发的最关键因素。  相似文献   

9.
硼、钙离子对杉木花粉萌发和花粉管生长影响   总被引:3,自引:0,他引:3  
采用固体培养法分析了蔗糖、硼酸和钙离子等花粉生长因子对杉木花粉萌发的影响.结果表明,适宜浓度的硼酸和钙离子对花粉的萌发有较大的促进作用,但当超过一定浓度时则起抑制作用.杉木花粉离体培养的最适硼酸和钙离子浓度分别为0.04 g/L和0.2 g/L,在5%蔗糖+0.04 g/L H3803+0.2 g/L Ca2++0.5%琼脂培养基上,杉木花粉萌发率为84.8%.  相似文献   

10.
采用固体培养基研究了不同浓度的蔗糖、硼和钙配比对杂交榛花粉萌发及花粉管生长的影响.结果表明:蔗糖、硼酸浓度间对花粉萌发有显著影响,钙浓度间对花粉萌发的促进作用不明显;蔗糖150 g·L~(-1)、硼酸100 mg·L~(-1)时最适宜花粉管伸长;蔗糖的缺乏会导致胼胝质在花粉管顶端积累,使其生长停滞,缺硼时胼胝质在花粉管内分布正常.杂交榛花粉适宜的培养基为:蔗糖150 g·L~(-1)+硼酸100 mg·L~(-1)氯化钙100 mg·L~(-1)琼脂10 g·L~(-1).  相似文献   

11.

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   

12.

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   

13.

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   

14.

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   

15.
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   

16.

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   

17.
18.

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   

19.
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   

20.
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   

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