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《竹子研究汇刊》2019,(3)
通过研究不同条件下笔竹的花粉活力以及柱头可授性,为笔竹的有性繁育及杂交育种工作提供理论参考依据,并为竹类植物生殖生物学积累相关资料。采用I_2-KI染色法、花粉离体培养基法测定笔竹花粉活力变化;采用联苯胺-过氧化氢法对不同开花阶段的柱头可授性进行测定。结果显示:笔竹新鲜花粉活性最强;1 d中笔竹花粉活性在3∶00 pm左右达到最高;不同浓度的蔗糖、硼酸配比对花粉萌发具有显著影响,笔竹花粉在10%蔗糖+0.01%硼酸浓度的培养基上培养3 h,萌发率最高;不同储藏条件对笔竹花粉萌发具有显著影响,而4℃湿藏条件下保存短时间内可延长花粉活力至120 h;柱头具可授性,可授期仅2～3 h,成熟期(散粉时期)柱头可授性最强。结论:笔竹花粉在10%蔗糖+0.01%硼酸的培养基内培养3 h萌发效果最好;1 d内尽量采集3∶00 pm左右的新鲜笔竹花粉对散粉时期的柱头进行人工授粉效果最好;新鲜花粉易失活,低温不干燥的储藏处理可以短时间内延长花粉寿命。 相似文献
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不同质量浓度的蔗糖和硼酸对北京杨花粉萌发的影响 总被引：3，自引：0，他引：3
以北京杨新鲜花粉为材料,研究固体培养基中蔗糖和硼酸不同质量浓度对花粉萌发的影响,结果表明:在培养基不含硼酸时,最适宜萌发的蔗糖质量浓度为10%,萌发率93.5%;当达到20%时,抑制花粉萌发,萌发率仅为55.6%。在培养基不含蔗糖时,最适宜萌发的硼酸质量浓度为0.01%,随着质量浓度升高,萌发率呈下降状态。在蔗糖和硼酸的双重作用下,最适宜萌发的质量浓度为10%蔗糖+0.01%硼酸,萌发率高达98.6%,花粉管生长快、健壮。新鲜花粉生活力测定的培养时间为24 h。 相似文献
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采用4种不同染色方法及培养基萌发法对5种花色的三色堇花粉生活力进行了测定。结果表明：I-KI染色法、醋酸洋红染色法和TTC染色法不适用于三色堇花粉生活力的测定,而过氧化物酶沉淀法与培养基萌发法是测定三色堇花粉生活力较好的方法;蔗糖和硼酸的浓度影响三色堇花粉的萌发,质量浓度分别为20mg/L、1.5mg/L蔗糖和硼酸对三色堇花粉萌发有很好的促进作用;花粉的生活力与贮藏条件也密切相关。 相似文献
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研究了云杉花粉在离体培养条件下,蔗糖浓度、pH值、贮藏条件对其萌发和花粉管生长的影响,同时还优化了培养基的组分配比。结果表明:培养基中蔗糖浓度和pH值对云杉花粉的萌发影响显著,并有明显的交互效应。蔗糖低浓度和高浓度都不利于云杉花粉的萌发。不同的云杉种对培养基中蔗糖浓度要求不同,粗枝云杉和欧洲云杉花粉萌发的适宜培养基的蔗糖浓度和pH值分别为7.5%、5.5,10%、5.5。在暗培养条件下,欧洲云杉花粉6 h开始萌发,粗枝云杉8 h开始萌发,欧洲云杉较粗枝云杉提早2 h,同时欧洲云杉花粉萌发率总体高于粗枝云杉;欧洲云杉花粉管的生长历程为20 22 h,而粗枝云杉为16 h左右;欧洲云杉的花粉管长度比粗枝云杉长10μm以上。2种云杉不同个体基因型间的花粉萌发率和花粉管长度存在极显著差异。贮藏方法对花粉的生活力有很大影响,在云杉花粉保存过程中温度是主要条件,冷冻比冷藏好,不宜常温保存。 相似文献
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以江西吉水种源的白花树花粉为研究材料,进行了扫描电子显微镜下的花粉形态结构观察以及采用离体培养基法、I2-KI和TTC染色等花粉生活力测定方法的比较研究,探讨了不同贮藏条件对花粉萌发的影响。研究结果表明:白花树花粉粒为长球型,具3孔沟,外壁面具细网状纹饰;花粉平均极轴长52.33±0.577μm,平均赤道轴长26.89±0.502μm;3种花粉生活力测定方法中以离体培养基法最有效,花粉萌发的最佳组合为:10%蔗糖+0.05 g·L-1硼酸+100 mg·L-1GA3+3 h;花粉最佳贮藏条件为-80℃密封保存,贮藏180 d后花粉的萌发率仍可达40.97%。 相似文献
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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
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《山东林业科技》2015,(1)
以金沙槭(Acer paxii Franch.)和三角枫(Acer buergerianum Miq.)为试验材料,蕾期采粉,并且采用TTC染色法和液体培养基离体萌发法对它们的新鲜花粉,室温条件下(25℃)和4℃冷藏条件下保存的两种花粉进行了生活力测定。结果表明:液体培养基中蔗糖浓度对花粉萌发具有明显影响,三角枫花粉的最佳萌发浓度为10%,而金沙槭花粉的最佳萌发浓度为15%;TTC染色法测定的花粉生活力比液体培养基离体萌发法测定的花粉生活力高;室温条件下(25℃)保存的金沙槭花粉4天后便失去了生活力,三角枫花粉6天后完全失去生活力;4℃低温保存条件下,金沙槭花粉的可贮藏时间较短,约40d后花粉便失去了生活力,而三角枫的花粉贮藏40d后的萌发率为31.37%。 相似文献
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通过使用不同的培养基,采用液体培养法研究了蔗糖、硼酸和钙离子对二乔木兰花粉萌发的影响。将所用花粉分为两组,组1于8:00采集,组2于16:00采集,结果表明:一定浓度的蔗糖、硼酸和钙离子对花粉的萌发有较大的促进作用,但超过一定浓度时则起抑制作用,二乔木兰花粉萌发的最适培养基为30 g·L~-1蔗糖 100mg·L~-1硼酸 500 mg·L~-1Ca~2 ,在该培养基内,组1花粉的萌发率为46．21%±1．86%,花粉管长度为1156．25Um;组2花粉的萌发率仅为14．22%±1．86%,花粉管长度为1022um。此外,在其离体萌发过程中,二乔木兰花粉存在花粉管双萌发的现象。用不同的花粉保存方法保存二乔木兰花粉后,发现干燥处理后于-18℃下保存的花粉活性最高,30d后仍有6．92%±0．75%的萌发率,而于常温25℃下保存的花粉10d后就基本失活,说明低温干燥保存是保存二乔木兰花粉活性的有效途径。 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(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
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《Scandinavian Journal of Forest Research》2012,27(2):166-178
This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes. 相似文献