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1.
杉木古树种质与现代优良无性系杂交配合力分析与选择   总被引:3,自引:1,他引:2  
以杉木古树无性系和杉木单亲子代测定优良无性系为亲本的杂交子代为研究对象,通过生长差异分析、配合力变量分析探求杉木古树遗传变异规律和价值潜力.结果表明杉木古树种质作父本进行杂交可取得理想结果.一般配合力对生长性状起主要控制作用,特殊配合力的控制作用甚微.一般配合力高的杉木古树亲本不一定能产生优良杂交组合,而一般配合力低的杉木古树亲本一定不能产生优良杂交组合.根据一般配合力相对效应值,选出‘三52'、‘三54'为杉木优良杂交母本,‘闽1'、"王混"为优良父本.再采用指数选择法选择出树高、胸径、材积遗传增益分别为3.12%、3.43%、15.46%的4个优良杂交组合及树高、胸径、材积遗传增益分别为9.09%、15.57%、63.18%的10株优良个体,这些优良杂交组合及个体在提高杉木生产力和丰富高世代育种群体种质资源中能起到重要作用.最后得出杉木古树种质资源有着巨大生产及种质潜力,应加以利用,从而提高现有杉木栽植材料的遗传品质的结论.  相似文献   

2.
马尾松巢式交配子代生长和木材基本密度遗传分析   总被引:2,自引:0,他引:2  
以浙江淳安县富溪林场马尾松巢式交配设计的12年生遗传测定林为试材,分析其生长和木材基本密度等主要经济性状父本/母本效应和加性/显性效应。结果表明:除树干通直度外,不同杂交组合间、父本间以及相同父本不同母本间的生长与木材基本密度等存在显著的遗传差异。胸径、树高和单株材积及树干圆满度同时受到父本和母本效应的影响,且二者效应差异较小,而木材基本密度则主要受母本效应的影响,其母本效应是父本效应的1.56倍。马尾松胸径和木材基本密度以加性效应控制为主,显性效应次之,而树高、单株材积和树干圆满度几乎完全由加性效应控制,可依据亲本表现对其子代进行预测。然而比较分析发现,不同杂交组合和父本无性系其生长与木材基本密度的相关性较小,速生的杂交组合和父本无性系并不一定具有较低木材基本密度。各杂交组合生长表现与父本无性系GCA之间相关性不明显,但选配GCA高的父本无性系将会提高获得优良组合的机率。以干物质积累量和胸径等为选择指标,分别选出纸浆纤维材和锯材各10个优良杂交组合,及17个和13个优良单株。  相似文献   

3.
关于杉木双列杂交试验若干问题的探讨   总被引:4,自引:1,他引:3       下载免费PDF全文
利用杉木9×9半双列和杉木6×6全双列试验材料,并综合我国杉木配合力育种中所有的文献资料,进一步探讨了杉木双列杂交试验和配合力测定中应注意的若干问题.结果表明:(1)生长发育阶段及试验环境对控制杉木性状的加性遗传方差和非加性遗传方差比值没有质的影响;(2)在I类材料中,杉木的母本细胞质效应作用不明显,在II类材料中,在选择性状(生长性状)上,检测到显著的母本细胞质效应,但这不影响非加性遗传方差份量的主导作用;(3)交配设计类型的变化对杉木II类材料的性状基因作用方式的试验结果有明显的影响;(4)在控制子代性状的表达方面,母本的加性效应显著,父本的花粉效应不明显,但父本与母本互作效应极其明显.因此在杉木杂交育种中,可以评选出具有突出表现的杂交组合.  相似文献   

4.
对杉木进行了优良家系选择;1.5代种子园建立技术;种子园施肥效果;遗传型与环境的交互效应和杉木多水平杂交效应的系列研究。研究结果为:1.以生长量、回归系数和遗传稳定度为指标,从5—11年生的414个测定家系申,以0.2的选择比率,选出优良家系86个,其材积增益较对照提高20—69%(或树高大于对照10—37%);2.用多性状指数选择方法,选出优良家系30个,以随机配置方式,建立杉木1.5代种子园100亩,材积遗传增益较初级种子园提高10%以上,并初步调整了贵州杉木基因资源群体、育种群体和种子生产群体结构不合理的状况;3.连续三年在黎平杉木初级种子园内进行了施肥试验。与不施肥比较,平圴提高杉球果产量8—31%,千粒重2.76%,发芽率8.09%,出籽粒7.18%。施肥的最佳季节是每年的6月中旬,其次是8月中旬;4.杉木遗传型与环境的交互效应以及年度的效应相当明显,不同立地条件具有各自不同的适生基因型,因此确定了所选优良家系的适生区和推广范围;5.杉木杂交试验结果表明:杉木3年生高生长的一般配合力高于特殊配合力;抗病性特殊配合力高于一般配合力。杉木杂交效应依次为:父本×母本/种源>母本/种源>父本×种源>父本>种源。  相似文献   

5.
【目的】测定尾叶桉与巨桉杂种F 1多年度的生长性状,估算其遗传参数,开展优良杂交组合及杂种优良单株选择,为桉树亲本选配和杂种应用提供科学依据。【方法】以尾叶桉与巨桉6×6析因交配F 1代杂种为材料,应用ASReml-R软件估算1、2、4.5、8.3和10.3年生时生长性状的遗传力、显性效应、加性效应、亲本效应和配合力等遗传参数;计算每个杂交组合单株材积的平均值,以所有组合的平均值+标准差为标准进行优良杂交组合选择;基于所有单株的材积,采用平均值+2倍标准差(标准Ⅰ)和平均值+3倍标准差(标准Ⅱ)2个标准进行杂种优良单株选择。【结果】尾巨桉F 1代杂种在各年龄时的生长表现均优于对照尾叶桉亲本自由授粉子代。每个年份树高、胸径和单株材积在组合间均存在极显著( P <0.01)或显著( P <0.05)差异,在区组间差异不显著。1年生和2年生时杂种各生长性状的母本加性方差分量低于父本加性方差分量, 4.5年生时父、母本加性方差分量较为接近,8.3和10.3年生时母本加性方差分量则高于父本加性方差分量。随年龄的增长,杂种的树高和胸径单株遗传力呈现由中度至低度遗传控制的变化趋势,杂种家系遗传力呈现高—中—低度遗传控制的趋势,且杂种家系遗传力大于单株遗传力。显性方差与加性方差的比值则随年龄的增长呈递增趋势。年-年和性状-性状双变量遗传、表型呈显著或极显著正相关。4.5年生时,母本U21及父本G8的一般杂交力(GHA)最高,U21×G5组合的特殊杂交力(SHA)最高;8.3年生时,母本U21及父本G19的GHA最高,U2×G19的SHA最高。【结论】尾巨桉F 1杂种1~2年生时父本效应大于母本效应,且加性效应大于显性效应,4.5年生时父、母本效应对杂种生长的贡献率相当,8.3~10.3年生时杂种的母本效应大于父本效应,且显性效应大于加性效应。同时评选出7个优良杂种,筛选出1个优良母本和2个优良父本,并依据标准Ⅰ、Ⅱ分别选出40株和16株优树,为今后大规模人工制种及推广应用提供可靠的亲本材料和优良无性系。  相似文献   

6.
杉木幼龄期种内杂种优势及遗传力的初步研究   总被引:1,自引:0,他引:1  
本文报道了杉木7个优良无性系3母本×4父本测交系交配设计幼龄期试验的初步结果:(1)杉木幼龄期的遗传力较小,苗期的遗传力低于定植1年后的遗传力,苗高h2N为21.04%,地径h2N为0;树高h2N为37.16%,h2B为41.53%,地径h2N为20.69%,h2B为45.91%。(2)杂种优势效应明显,最高达32.02%,杂种优势变幅大,为—33.39%—32.03%。(3)在第一代种子园亲本间再行控制杂交,能进一步获得具有显著效应的杂交组合,供高世代育种用。  相似文献   

7.
岑软2号、3号等油茶无性系花粉配合力测定   总被引:1,自引:0,他引:1  
采用全双列交配设计,完成油茶(Camellia oleifera)6个无性系间的花粉配合力测定,筛选出17个高配合力组合,其中以岑软3号×岑软2号为最高,座果率高达92.0%.以桂软24号为母本,分别以桂软1号、岑软3号、桂软11号和桂软22号为父本的杂交果鲜出籽率均在40%以上,品质优良;桂软22×岑软2的杂交组合所得杂交果的出籽率也较高,为43.15%.  相似文献   

8.
为揭示杉木高世代杂交子代生长与材性性状的遗传效应,选择优良的杂交组合,利用设置在浙江省开化县林场的4×5双因素交叉设计的杉木高世代杂交子代测定林,研究8年生杉木的生长性状、木材基本密度和树干碳含量,估算各性状一般配合力(GCA)/特殊配合力(SCA)效应值及相对重要性,分析遗传控制方式及性状间的相关性。结果表明:杉木树高、胸径、单株材积、木材基本密度、树干碳含量在杂交组合间均差异显著(P<0.05),含碳率在组合间差异不显著。父母本配合力分析显示,树高、胸径、单株材积、树干碳含量的母本效应均大于父本效应,C25-3母本效应最大,B109-3父本效应最大;杂交组合各性状均以加性基因效应控制为主,杉木高世代育种工作仍需注重亲本的选配。性状间相关性分析表明,树干碳含量与生长性状呈显著正相关,按10%的入选率,联合选择出3211和3215两个速生高固碳的杂交组合,单株材积较对照(CK)增加30.91%以上,树干碳含量较CK增加26.95%以上,而木材基本密度与生长性状呈弱相关或负相关,筛选出3218和3216两个木材性状优良的杂交组合,木材基本密度较CK增加2.17%以上。  相似文献   

9.
为筛选适合湘东低山丘陵区种植的杉木良种,以6种不同类型不同世代的杉木良种为试验材料(分别为福建洋口林场杉木3代种子园混系实生苗、福建优良杉木无性系洋020组培苗、湖南杉木2代种子园混系实生苗、湖南杉木1.5代种子园混系实生苗、湖南杉木1代种子园混系实生苗、湖南普通杉木人工林林分种子实生苗)营造试验林。结果表明:在6年生、8年生时,不同类型不同世代良种间平均树高、胸径和材积存在显著或极显著差异。在8年生时,湖南2代杉木良种材积最大,其均值为0.088 2 m~3,比对照大120.0%;其次是福建3代杉木良种和福建无性系,材积均值分别为0.085 8 m~3和0.085 4 m~3;福建无性系变异系数最小,为26.57%。杉木高世代良种具有明显的增产效果,选择本地选育的杉木良种造林能取得较好的增产效益。  相似文献   

10.
对 10年生杉木不同种源优系 5× 5双因素交叉式遗传设计试验林的胸径和木材比重两性状进行了测定和遗传分析。结果表明 ,两性状在组合间均达极显著差异 ,组合内亲本的一般配合力和杂交的特殊配合力亦达显著差异水平。胸径的一般配合力方差分量为 70 32 % ,而木材比重的一般配合力方差分量则为 5 3 84 % ,胸径、木材比重广义遗传力分别为 4 2 4 9%和6 9 6 0 % ,狭义遗传力分别为 2 9 88%和 37 0 0 %。亲本川 15、闽 4、湘 6、粤 11对胸径生长有较高一般配合力正向效应值 ,同时亲本闽 4对木材比重亦有较高的一般配合力正向效应值。另有 4个杂交组合浙 13×浙 8、湘 30×川 18、闽 16×湘 6、川15×闽 4对胸径生长有较高的特殊配合力正向效应值 ,对胸径和木材比重均表现出正向效应的只有闽 16×川 18和粤 5×湘 6组合  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.
17.

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   

18.
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   

19.
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   

20.

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   

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