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1.
杉木改良代无性系种子园子代测定林营建与评价 总被引：1，自引：0，他引：1
以阳新县七峰山林场杉木改良代无性系种子园自由授粉子代半同胞家系为研究对象,分析其树高、胸径、材积等生长性状,发现家系间存在极显著差异,说明杉木改良代无性种子园半同胞家系,经初级种子园子代测定林的选择,仍存在着较为丰富的变异,具选育潜力。其树高、胸径和材积间呈紧密相关关系。树高、胸径和材积的家系遗传力分别是0.4187、0.3315、0.4988,单株遗传力分别是0.2113、0.1329、0.2494,均为材积>树高>胸径,具有较强遗传力。按照33.3%的入选率,树高、胸径和材积入选10个家系均相同,其遗传增益分别是6.15%、7.21%、26.06%,可作为营建高世代种子园和进行人工交配进行全同胞测定的优良家系。 相似文献
2.
马尾松无性系种子园半同胞子代变异分析和家系选择 总被引：13，自引：0，他引：13
以福建省漳平五一林场马尾松无性系种子园自由授粉子代半同胞家系为研究对象,分析其树高、胸径、材积、冠幅、通直度、高径比、冠径比、木材基本密度、管胞长度和宽度、管胞长宽比等性状,发现家系间除管胞长宽比性状差异显著,其余性状均达差异极显著,暗示着马尾松种子园半同胞家系间存在较为丰富的变异,具选育潜力。8年生林分内各性状的家系遗传力以树高性状为最高(0·691),其次是木材基本密度(0·640)。各性状间的相关性分析结果表明,生长量性状的改良可间接改善通直度,且生长量性状与木材基本密度存在显著正相关关系,木材基本密度与管胞长度和宽度不相关。采用10%入选率,发现5年生林分和8年生林分入选家系一致,材积遗传增益分别达19·74%和19·23%,且5年生林分和8年生林分生长量性状的遗传相关极显著,认为马尾松制浆造纸材短轮伐期的初选年龄可确定为5年生;根据性状遗传力的相对大小和典型相关分析的结果,认为马尾松家系选择可适当注重树高生长量指标。以树高和材积为选择指标,按照10%入选率,兼顾材性和种子园内无性系的开花结实情况,筛选出制浆造纸材短轮伐期优良家系12个。 相似文献
3.
Variation of traits that include height, diameter at breast height (DBH), stem volume, crown width, straightness, wood basic
density, tracheid length and width of open-pollinated progenies from clonal seed orchard of Pinus massoniana was analyzed. Differences in traits such as growth, tree form and wood quality among families was significant, which indicated
that the improvement potential was notable. Heritability of height and wood basic density reached 0.691 and 0.640, respectively.
According to a correlation analysis between traits, stem straightness could be improved indirectly when growth traits are
improved; growth traits were significantly correlated with wood basic density; and wood basic density was not significantly
correlated with length and width of the tracheid. Under the selection ratio of 10%, genetic gains were 19.74% and 19.32% respectively,
and selected families from the progeny test stands at the age of five years and eight years were the same. Genetic correlation
of height, DBH and stem volume was also significant at the level of 0.01. These show that selection of the short rotation
of P. massoniana for pulp and paper use would be efficient for five-year-old trees. According to the comparison of the heritability of all
the traits and taking into account the result of canonical correlation analysis, height could be considered as the most important
index for selection. Given wood quality of all the families, and flowering and fruit settings of the clones in a seed orchard,
twelve fine families were selected at 10% selection ratio of height growth and stem volume.
Translated from Scientia Silvae Sinicae, 2005, 41(6): 43–49 [译自: 林业科学] 相似文献
4.
以海南2个试验点上各含17个无性系的短枝木麻黄无性系为试验材料,进行树高、胸径、单株材积、主干分叉习性、主干通直度和保存率等6个性状的方差分析,并估算出6个性状的遗传相关和遗传力及指数选择等遗传参数。结果表明:无性系和地点的交互作用除了主干分叉习性有显著差异(p0.05)外,其他性状在无性系间差异均极显著(p0.001)。当不考虑无性系和地点互作时,无性系间不同性状的重复力均较高,为0.35 0.85,其中,树高重复力最高,主干分叉习性最低。遗传相关分析结果表明:树高、胸径、单株材积和保存率之间的表型及遗传存在极显著的正相关。树高、胸径、单株材积、主干分叉习性、主干通直度和保存率的平均遗传增益分别为6.5%、4.8%、10.9%、3.7%、1.5%和8.1%,筛选可获得明显的遗传增益。通过Smith-Hazel指数选择并按20%的入选率,选育出编号17、21和20三个优良无性系。 相似文献
5.
以福建省白砂国有林场的马尾松实生种子园自由授粉子代测定林为材料,分析了5、6年生家系生长量(树高、胸径及材积)及形质指标(通直度、冠幅及侧枝粗度)的遗传变异规律,估算了各性状的遗传力。结果表明,材积、胸径、树高生长性状及冠幅、通直度、侧枝粗度等形质指标在家系间和家系内均存在显著的遗传差异,且家系内变异大于家系间。家系、单株遗传力分别在0.493 0.731、0.080 0.199之间。利用最佳线性预测的单性状(材积)及多性状联合(材积、冠幅、侧枝粗度及通直度)估算了6年生家系育种值。分析了材积单性状选择方式、多形状联合选择以及冠幅约束选择在不同入选率下亲本家系的预测及现实遗传增益(材积及通直度)的变化规律,结果表明,在等权重条件下,联合材积及通直度指标进行亲本家系选择是最佳选择方式,能够获得相对较高的遗传增益。 相似文献
6.
Belaber Ector C. Gauchat María E. Rodríguez Gustavo H. Borralho Nuno M. Cappa Eduardo P. 《New Forests》2019,50(4):605-627
Non-spatial and spatial analyses were carried out to estimate genetic parameters for growth and stem straightness traits between ages 4 and 7 in two series of eight progeny trials of Pinus elliottii Engelm. var. elliottii (PEE) established in 2004 and 2008, comprising 429 open-pollinated families from Instituto Nacional de Tecnología Agropecuaria (INTA) tree breeding population in Argentina. A first-order autoregressive spatial mixed model was found to significantly improve the fit of the model, compared with the standard non-spatial mixed model approach, due to substantial spatial heterogeneity within sites. The average individual-tree narrow-sense heritability estimates based on this spatial analysis were 0.49 for diameter at breast height, 0.36 for total height, and 0.48 for volume, with stem straightness being low to moderate (average?=?0.11). The additive genetic correlation estimates between growth traits were positive (0.51?≤?\(\hat{r}_{a}\)?≤?0.99) and statistically significant from zero. In contrast, the genetic correlations between growth traits and stem straightness although in general also positive were not significantly different from zero (??0.22?≤?\(\hat{r}_{a}\)?≤?0.59). Age-to-age genetic correlations were consistently higher for growth traits (\(\hat{r}_{a}\)?≥?0.81) than for stem straightness (\(\hat{r}_{a}\)?≥?0.33). The average additive genetic correlation estimated between sites within test series was high for all traits evaluated (average?>?0.72). In contrast, average additive genetic correlation estimated between sites across series was slightly lower (average?<?0.63). Implications of all these parameter estimates for genetic improvement of PEE in Argentina are discussed.
相似文献7.
Realized genetic gains brought by the first-generation tree improvement of Acacia mangium were evaluated by analyzing the 1-year growth performance of growth (height, dbh) and form (stem straightness, multi-stem) traits using data collected from three second-generation orchards: groups B, C, and D. Each orchard was composed of improved families derived from open-pollinated seed of plus trees selected from the first-generation seed orchards and newly added unimproved families collected from the same geographic region. The number of improved families and that of the unimproved in each orchard were 31 and 23 for group B, 28 and 39 for group C, and 24 and 30 for group D. Gains were calculated as percentage increase of improved families over unimproved ones. Improved families performed better than unimproved ones in 11 out of 12 comparison cases: four traits each in the three orchards. Averages of the realized genetic gain across the three seedling seed orchards were 3.1%, 5.2%, 4.3%, and 0.5% for height, dbh, stem straightness, and multi-stem, respectively. Except for multi-stem, the performances of improved families were significantly better than those of unimproved families in all the three orchards for dbh and in two out of three orchards for height and stem straightness. 相似文献
8.
Individual and family heritabilities, as well as phenotypic and genetic correlations were estimated 2 and 3 years after plantation,
in progeny tests carried out in plantations of open-pollinated Pinus radiata D.Don progeny located at three different sites in Galicia (NW Spain). The following factors were considered: survival, growth
(free growth, height, diameter, volume, height/diameter ratio), form (number of branches, number of whorls, number of branches
per whorl, number of branches per tree height meter, number of ramicorn branches, diameter of the thickest branch, internode
length, branch angle, stem straightness, stem sinuosity, number of forks) and resistance (frost and insect resistance). Each
plantation contained 50 female parents that had been selected as plus trees in genetically unimproved plantations in Galicia,
as well as 6 female parents selected from the radiata pine breeding programme in the Basque Country (northern Spain) and two
commercial lots of seed from Galicia, as controls. Individual heritabilities varied from low to high levels for each trait
studied. Family heritabilities followed similar trends for individual heritabilities, but were of much greater magnitude.
The results suggested that all traits except the number of branches per whorl and insect resistance could be expected to respond
to selection based on individual performance. The less heritable traits could be improved by progeny testing. Height and diameter
were strongly and positively correlated, and both traits were also correlated with the number of branches, the number of whorls
and the branch diameter. The results are compared with previously published data and discussed in relation to the implications
for breeding activities. 相似文献
9.
对位于浙西北的９年生湿地松自由授粉子代测定林进行了生长性状的逐年观测和７年生时形质调查及材性测定，估算了遗传参数。各家系间的高、径生长和干形、分枝角等性状表现出显著的差异，家系平均遗传力也都达中等程度以上（ｈ２ｆ＞０．４）。对生长性状进行了年度相关和早晚期选择效率分析，表明第５～７年是适宜的早期选择年龄。据树高、胸径、树干通直度、分枝角度四种性状建立的多性状选择指数表明，不可能对它们进行同步改良，生长性状应是主要选择因素。在等权重情况下，对通直度和分枝用进行约束，选择出三个以建筑材为目的的优良家系。 相似文献
10.
Second-generation plus tree selections were assessed in three genetic tests of sugi (Cryptomeria japonica) in Kyushu: at Kumamoto, Saga, and Miyazaki. The selections were made by private foresters choosing good trees according to their own preferences when the tests were around 30 years of age. A retrospective selection index applied to the results of selection revealed that the foresters had put more emphasis on stem straightness than on growth. This trend was particularly evident at Kumamoto, whereas the foresters at Miyazaki and Saga had allocated nearly the same weight to growth as to stem straightness. Broad-sense heritabilities on dbh, stem straightness and bottom stem crookedness were 0.226, 0.256, and 0.206, respectively. These estimates were regarded as almost the same as narrow-sense heritabilities, because non-additive genetic variances were found to be small. Relative gains, assuming that the selections are propagated with rooted cuttings, were predicted to be around 10% for stem straightness, 7% for bottom-stem crookedness, while the gains on dbh were variable among the tests: ranging from 3% at Kumamoto up to around 8% at Saga and Miyazaki. 相似文献
11.
Sierra-de-Grado R Pando V Martínez-Zurimendi P Peñalvo A Báscones E Moulia B 《Tree physiology》2008,28(6):835-846
Stem straightness is an important selection trait in Pinus pinaster Ait. breeding programs. Despite the stability of stem straightness rankings in provenance trials, the efficiency of breeding programs based on a quantitative index of stem straightness remains low. An alternative approach is to analyze biomechanical processes that underlie stem form. The rationale for this selection method is that genetic differences in the biomechanical processes that maintain stem straightness in young plants will continue to control stem form throughout the life of the tree. We analyzed the components contributing most to genetic differences among provenances in stem straightening processes by kinetic analysis and with a biomechanical model defining the interactions between the variables involved (Fournier's model). This framework was tested on three P. pinaster provenances differing in adult stem straightness and growth. One-year-old plants were tilted at 45 degrees, and individual stem positions and sizes were recorded weekly for 5 months. We measured the radial extension of reaction wood and the anatomical features of wood cells in serial stem cross sections. The integral effect of reaction wood on stem leaning was computed with Fournier's model. Responses driven by both primary and secondary growth were involved in the stem straightening process, but secondary-growth-driven responses accounted for most differences among provenances. Plants from the straight-stemmed provenance showed a greater capacity for stem straightening than plants from the sinuous provenances mainly because of (1) more efficient reaction wood (higher maturation strains) and (2) more pronounced secondary-growth-driven autotropic decurving. These two process-based traits are thus good candidates for early selection of stem straightness, but additional tests on a greater number of genotypes over a longer period are required. 相似文献
12.
13.
对红锥(Castanopsis hystrix) 1.5代改良种子园42个无性系共951个单株的生长和形质性状进行调查和变异规律研究.结果表明,8个性状的变异系数为25％～47％,平均变异系数为32.6％.无性系间在生长和形质性状上的差异达显著和极显著水平(P＜0.05),无性系间的方差分量为0.04～13.15.树高、胸径、冠幅、分枝角度、分枝数和分枝粗细的重复力介于0.23～0.34之间,表明它们在单株水平上受到中等水平的遗传控制.生长和形质性状相关分析表明,除通直度与冠幅、分枝数相关系数以及分枝粗细与分枝角度相关系数较低外,各性状间存在着不同程度的相关性.采用遗传值综合评分法筛选出6个优良无性系:28、3、4、23、33和22,这6个优良无性系的胸径比42个无性系总体平均值高出24.11％. 相似文献
14.
S. N. Aitken W. T. Adams N. Schermann L. H. Fuchigami 《Forest Ecology and Management》1996,80(1-3):187-195
In order to assess the genetics of fall cold hardiness in coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco), shoot cuttings were collected in October from saplings (9-year-old trees) of open-pollinated families in two progeny tests in each of two breeding zones in Washington, one in the Coast range (80 families) and one on the west slope of the Cascade Mountains (89 families). Samples from over 5500 trees were subjected to artificial freezing and visually evaluated for needle, stem and bud tissue injury. The extent to which cold injury is genetically related to tree height and shoot phenology (timing of bud burst and bud set) was also evaluated.
Significant family variation was found for all cold hardiness traits; however, individual heritability estimates were relatively low (ranging from 0.09 to 0.22). Significant family-by-test site interaction was detected for needle injury in the Cascade breeding zone, but not in the coastal zone. Genetic correlations (rA) among needle, stem and bud tissues for cold damage were weak (0.16 ≤ rA ≤ 0.58) indicating that genes controlling fall hardening are somewhat different for different tissues. Timing of bud burst and bud set were only weakly correlated with cold injury (rA ≤ 0.49). Thus, bud phenology is a poor predictor of fall cold hardiness in this species. There was no consistent relationship between tree height and cold injury in the coastal zone. In the Cascade zone, taller trees appeared to be more susceptible to cold injury, but the association was weak (mean rA = 0.38, range 0.20 – 0.72). 相似文献
15.
根据 10年生湿地松 6× 6半双列子代在两个试验地点的生长量、木材基本密度、树干通直度和抗风性数据 ,研究了该树种目的性状的遗传变异规律。结果表明 ,地点间存在着显著的生长差异和通直度差异 ,但两点的木材基本密度非常一致 ;所有研究性状均存在着一定程度的地点与基因型互作 ,其中胸径、基本密度均达到了显著以上水平 ;在一般配合力 (GCA)均方差显著地大于特殊配合力 (SCA)均方差的前提下 ,胸径、材积、基本密度、通直度、抗风性的加性方差占总遗传方差的 96 .4 1%～ 10 0 %。但是 ,树高性状以非加性方差居优。决定子代表现的遗传因素 ,主要是亲本的GCA,SCA和反交效应也有影响 ,但程度较低 ;两块测定林中 ,树高、胸径、材积、基本密度、通直度、抗风性的单株狭义遗传力分别为 0 .0 0 1和 0 .0 74、0 .0 80和 0 .144、0 .0 6 8和 0 .137、0 .10 8和 0 .6 0 9、0 .0 5 2和 0 .2 5 2、0 .0 5 8(单地点 )。 相似文献
16.
《林业研究》2021,(5)
The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_i~2) of height,DBH and volume growth were0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_i~2 of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species. 相似文献
17.
《湖北林业科技》2012,(6)
1991～1992年从湖北省马尾松主要分布区选出116株优良单株,1994年建立了相应的半同胞子代测定林。2011年对子代测定林生长性状、通直度、树皮厚度指数、弹性模量等进行了调查和分析。结果表明:树高、胸径、材积和弹性模量等4个性状在家系间都存在极显著的差异,也表明各优树之间存在广泛变异。树高、胸径和材积的家系遗传力分别为0.689、0.729和0.791,均大于单株遗传力,表明:各家系的主要生长性状受到较强的遗传控制,对参试家系进行选择,能取得比较理想的结果。弹性模量家系遗传力为0.507,属于中等程度的遗传,而树皮厚度指数这一指标家系遗传力较低。按照大于整体平均值加1倍标准差进行选择,树高、胸径、材积和弹性模量4个性状分别有14、14、15和14个家系入选,遗传增益分别为6.4%、11.1%、28.1%和6.6%。 相似文献
18.
Phenotypic, genotypic and environmental correlations between 10 growth and form characteristics ofEucalyptus camaldulensis Dehnh. grown at two locations within the Northern Guinea Savanna zone of Nigeria were investigated. These characteristics were tree height, diameter at breast height (dbh), number of branches and taper. Tree height and dbh were positively correlated with all the form characteristics except taper, which had positive correlations with tree height but negative correlations with dbh. Trees with better stem straightness tended to develop big-diameter branches that made relatively wide angles with the tree hole. Branch diameter had positive correlations with number of branches. Growth ofE. camaldulensis can be improved simultaneously with its first fork height, stem form and branch angle. However, in the improvement programme, the selection pressure has to be maintained on the other characteristics because of the unfavourable correlations between them and the two growth characteristics. 相似文献
19.
Natural black poplar (Populus nigra L.) clones sampled from river courses were tested in the arid southeast region of Turkey, using a randomized complete block field design with four replications. Clones were laid out in row plots of eight ramets each. Height and apical dominance were assessed at age one year; diameter, survival, bole straightness and branchiness were measured at age two years. Clones differed significantly in survival, growth and quality traits. The results showed that promising clones exist in natural populations. Two commercial clones out of four did not grow as fast as the top new selection clones. For bole straightness, three commercial clones had significantly lower grading scores than the top best 14 clones. Principal components analysis indicated that growth, apical dominance and branching are the most important traits distinguishing black poplar clones. Diameter had a moderate correlation (0.34) with bole straightness. Relationships between geographic variables (elevation, latitude and longitude) with growth and stem quality traits were weak. Considerable genetic variation was observed among clones for all the traits. Genetic differences among the clones accounted for 27% (survival, bole straightness) to 39% (height) of the total variance. Broad-sense individual heritability ranged from 0.27 (survival) to 0.37 (apical dominance). Clonal mean heritabilities were higher than individual heritabilities and ranged from 0.60 (survival) to 0.82 (diameter), implying considerable gain could be realized via selective improvement methods. 相似文献
20.
以福建省华安县西陂林场的25年生来自省内不同产地的46个马尾松自由授粉家系试验林为试材,研究了达主伐年龄时马尾松生长、干形和木材基本密度的家系差异以及性状间的相关性,并依据不同培育目标选择优良家系。结果表明,马尾松生长、树干圆满度和木材基本密度皆存在显著的家系差异,其中生长和树干通直度变异相对较大,而树干圆满度和木材基本密度变异较小,变异系数在10%以下。生长和干形性状受到弱至中度的家系遗传控制,家系遗传力为0.23 0.46;木材密度受到的遗传控制相对较强,家系遗传力为0.46。性状遗传相关分析结果显示,选择速生种源可同时改良树干圆满度,但对树干通直度和木材基本密度影响不大。根据不同用材对材质材性要求,选出24个纸浆纤维材优良家系和6个锯材优良家系,平均木材干物质量和胸径生长皆为对照的1.16倍。 相似文献