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1.
7种油茶花粉数量及花粉萌发率的测定   总被引：6，自引：1，他引：5  
以普通油茶、红皮糙果茶、博白大果、茶梨、越南油茶、大花红山茶和攸县油茶的花粉为材料,研究了花药内花粉数量和花粉离体培养萌发率.结果表明:7种油茶的单花药花粉平均数量分别为2 498、3 503.7、9 441.3、3 331.3、8 397.7、3 985.7、3 141.3粒,普通油茶、红皮糙果茶、博白大果和茶梨的花粉在10 g·L-1琼脂+0.1 g·L-1硼酸+100 g·L-1蔗糖的培养基上萌发率最高,萌发率分别为59.4%、56.3%、92.7%、95.3%;越南油茶、大花红山茶和攸县油茶的花粉在10 g·L-1琼脂+0.1 g·L-1硼酸+50 g·L-1蔗糖的培养基上萌发率最高,萌发率分别为39.6%、62.1%、72.1%.  相似文献   

2.
以普通油茶、小果油茶、越南油茶、攸县油茶、腾冲红花油茶、宛田红花油茶、浙江红花油茶、广宁红花油茶8个油茶物种为实验材料,初步研究了低温(4℃)预处理方法对油茶花药愈伤组织诱导效率的影响.结果得出,低温预处理有利于油茶花药愈伤组织的诱导,但不同的油茶物种最适宜的预处理时间不同,普通油茶为10 d左右,攸县油茶为5～10 d,越南油茶为15 d左右,浙江红花油茶为10 d左右,广宁红花油茶为15 d左右,腾冲红花油茶为10 d左右,宛田红花油茶为15 d;小果油茶经过低温预处理诱导率没有明显提高;普通油茶和小果油茶的花药愈伤组织诱导效率均达到了70%以上,可以作为花药培养的桥梁物种在以后的研究及技术推广中加以应用.  相似文献   

3.
研究了花粉的形态、数量与花粉萌发及贮藏条件。结果表明:黄连木花粉为单粒,球形或近球形,花粉粒大小整齐,平均直径为28.7μm;饱满花粉粒达95%以上;每花药平均花粉量为1.17×105粒。黄连木花粉萌发培养基中蔗糖浓度15%,硼酸为100mg/L,温度为25℃时萌发率最高,为79.43%;蔗糖浓度20%时,萌发率降低到77.27%。分别在4℃、-20℃、-40℃下干燥贮藏15d的花粉萌发率分别为78.74%、38.22%、27.20%,花粉管长度分别为126μm、230μm、293μm;贮藏25d的花粉萌发率分别为0、22.84%、2.00%,花粉管长度分别为0μm、195μm和132μm。  相似文献   

4.
香椿花粉离体萌发与花粉生活力研究   总被引：1，自引：1，他引：0       下载免费PDF全文
[目的]探究香椿花粉最佳离体培养条件,花药大小、含水率与花粉萌发率的关系及花粉生活力随低温贮藏时间的变化的规律。[方法]以3个不同基因型(XC5、XC22、ZJ26)香椿花粉为试验材料,观测不同培养温度(20、22、25、28℃)、培养时间(4、6、12、18、30、42 h)下,花粉离体培养的萌发率,获得香椿花粉最佳培养条件。对香椿的花药含水率、花药长、宽进行测量,分析其与花粉萌发率的关系。基于最佳培养条件,检测香椿花粉-20℃低温贮藏10、25、40 d的萌发情况,分析花粉生活力随低温贮藏天数的变化趋势。[结果]香椿花粉在20℃的萌发率均显著高于其余3个培养温度,花粉萌发率随培养时间的延长而增大,培养30 h后,花粉萌发率均无显著变化。低温贮藏10 d的花粉萌发率与花药长度显著正相关,与花药宽度显著负相关,相关系数分别为0.529 6、-0.739 9。随着低温贮藏时间的延长,香椿花粉萌发率显著降低,含水率高的XC22降幅最大,低温贮藏10、25 d的花粉萌发率分别为89.2%、3.3%。[结论]检测香椿花粉生活力的最佳离体培养条件为20℃培养30 h;香椿花粉萌发率与花药长度、宽度以及含水率可能作为筛选花粉高萌发率的指标;低温贮藏可能对含水率高的香椿花粉生活力影响大。  相似文献   

5.
贮藏条件对赣无系列油茶花粉活力和萌发率的影响   总被引：1，自引：0，他引：1  
为克服油茶杂交育种的花期不遇,用TTC法对赣无系列等26个油茶优良无性系的花粉活力进行简单快速测定,研究了不同贮藏条件对5个油茶优良无性系(赣无1、白皮中子、赣无16、赣无8、赣190)花粉活力的影响,以恒丰8号和闪光红山茶为试验材料,在-20℃真空冷冻条件下,附加干燥条件做进一步试验。结果表明:26个油茶优良无性系中,花粉活力最高的为赣70,达到93.16%;花粉活力在70%以上的油茶优良无性系共有18个,占所测总数的69.23%。在-20℃冷冻条件下,真空保存的花粉能在较长时间内保持较高的萌发率,赣无1在110 d时的花粉萌发率为36.13%,赣190在50 d时的萌发率为27.43%。在272 d时,闪光红山茶和恒丰8号的花粉萌发率仍分别高达39.12%和44.00%。可见,-20℃冷冻真空保存为花粉长期贮藏的有效方法。  相似文献   

6.
4个油茶优良无性系花器特征及花粉萌发率   总被引：1，自引：0，他引：1  
以怀化地区选育的怀06062、怀06018、怀06175、怀06122这4个油茶优良无性系花朵及花粉为试材,研究了油茶花的生物学特性、花粉数量和花粉萌发率。结果表明:怀06062、怀06018、怀06175、怀06122单花药花粉平均数量分别为2 566.7、2 000.0、4 450.0和2 350.0粒;怀06062和怀06175的花粉在5%蔗糖+0.01%硼酸+1%琼脂的培养基上萌发率最高,萌发率分别为94.31%和87.71%;怀06018的花粉在10%蔗糖+0.01%硼酸+1%琼脂的培养基上萌发率最高,为90.22%;怀06122的花粉在10%蔗糖+0.005%硼酸+1%琼脂的培养基上萌发率最高,萌发率为40.70%。  相似文献   

7.
为阐明广宁红花油茶授粉特性,提高其产量和效益,采取野外实地调查与实验室观测相结合的方法,研究了其花粉数量、活力、储藏条件、柱头可授性及辅助授粉效果。结果表明:(1)广宁红花油茶单枚花药花粉数在3 120~12 460粒之间,平均值为6 877粒;单花花粉数量随其花药花粉量增加而增加,在792 200~3 468 400粒之间,平均值为2 102 250粒。(2)花药多在开花第1天开始散粉,开花当天花粉活力随时间进程呈上升趋势,第2天达到最大值,前3 d花粉活力都在80%以上。而柱头可授性在花后第2天达到最大值,2~3 d是柱头可授性最强的时期,即最佳授粉时间。(3)花粉的最佳贮藏方式是-80℃处理,60 d内其活力仍保持在80%以上。(4)在自然授粉条件下,其结实率较低,自花结实率为3.26%;经过人工异株授粉后,结实率提高近2倍。  相似文献   

8.
油茶12个物种花药愈伤组织诱导及继代培养   总被引：2，自引：0，他引：2  
选择12个油茶物种进行花药愈伤组织的诱导,以小果油茶、普通油茶、短柱油茶、浙江红花油茶、茶陵红花油茶、多齿红花油茶诱导率较高,在40％～70％之间,其中小果油茶、普通油茶的愈伤组织诱导率高达70％。红皮糙果油茶、广西糙果油茶、茶陵红花油茶、多齿红花油茶、攸县油茶花药褐化较严重。继代培养中6-BA和KT均有较好的促进作用,小果油茶、普通油茶、短柱油茶、浙江红花油茶、茶陵红花油茶、多齿红花油茶的愈伤组织均增殖较好。油茶花药培养应以小果油茶、普通油茶、短柱油茶、浙江红花油茶、茶陵红花油茶、多齿红花油茶作为进一步试验的基本材料,开展下一步的愈伤组织增殖和脱分化试验。  相似文献   

9.
[目的]探究高州油茶花粉特征。[方法]通过纤维素酶法、扫描电镜法、养分测定、TTC染色法等方法对花粉数量、花粉形态、花粉养分含量及花粉贮藏特征进行研究。[结果]表明:(1)单枚花药的花粉量平均为2 699粒,单花花粉数平均为461 186粒;(2)高州油茶花粉大小属中等水平,极轴长44.66～54.08μm,赤道轴长27.38～34.29μm,呈长球形,赤道面观为长椭圆形,极面观为三裂圆形,花粉萌发孔在正常状态下为三(拟)孔沟型;(3)高州油茶花粉养分中全N、全P、全K、全Ca、全Mg、全Zn和全B的含量分别为58.72、7.73、8.65、1.94、1.22 g·kg~(-1)和135.93、2.73 mg·kg~(-1),全N、全P、全K、全Ca的含量与‘岑软2号’的差异不明显,全Zn和全B含量与‘岑软2号’的差异明显;(4)低温、干燥条件有利于高州油茶花粉的贮藏,4℃干燥贮藏60 d后花粉生活力保持在80%以上,-20℃干燥、-80℃干燥贮藏360 d后花粉生活力仍在30%以上。  相似文献   

10.
为了研究油茶花粉贮藏特性及品系间杂交亲和性规律,选取‘长林3号’、‘长林166号’、‘长林4号’、‘湘林8号’、‘岑软3号’共5个油茶无性系花粉进行贮藏特性及人工杂交亲和性研究,通过对不同贮藏条件下花粉萌发率的对比及不同杂交组合杂交座果率的统计与分析,发现随着贮藏时间延长,花粉生活力呈明显下降趋势,油茶花粉最佳贮藏方式为冷冻干燥贮藏,‘长林3号’、‘长林166号’油茶无性系花粉冷冻贮藏90d后花粉萌发率均具45%以上,室温干燥保存50d后花粉全部失活,低温干燥保存90d后花粉萌发率均比冷冻干燥保存下花粉萌发率低10%左右;6个杂交组合中亲和力较好的组合为:♀湘林8号×♂长林3号、♀长林4号×♂长林3号、♀湘林8号×♂长林166号、♀长林166号×♂岑软3号3月份座果率分别为40%、44%、48%、52%。  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.
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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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