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研究了８年生杉木无性系试验林的树高、胸径、材积和木材密度的遗传变异规律。结果表明：试验中各性状在无性系间存在显著差异，遗传变异系数树高为９０％，胸径为１３７％，材积为３００％，而木材密度只有６７％，各性状均有较高的重复力，木材密度和胸径的重复力在９００％以上。树高、胸径、材积３个生长性状间有较高的遗传正相关，而胸径、材积与木材密度间表现出中度的遗传负相关，树高与木材密度间则表现出弱度的遗传负相关。采用简化的指数选择法评选出４个优良的无性系，材积现实增益２５５２％，遗传增益２１０５％，用木材密度与ＣＫ相近。 相似文献
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杉木８２个无性系间１－４年生树高差异极显著，生长量最大相差达１．６－２．７倍。遗传变异系１２．５－２２．８％，广义遗传力估值０．６３３－０．９４１，遗传变异幅度和遗传控制程度都有随树龄增大而变小的趋向。按１０％的入选率，中选无性系的树高平衡遗传增益可达２５％左右，但无性系相对于种子园子代的树高生长优势可能因树龄小而尚水表达出来，２年生与３进行了分析和讨论，认为以提高木材产量为目标选择优良无性系的工 相似文献
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对河北、河南、山东、甘肃的４块毛白杨无性系测定林中约１００个无性系进行了木材基本密度的测定，对木材基本密度在地点和无性系间的遗传变异进行了研究．结果表明：毛白杨无性系的木材基本密度平均值为０．４３６３ｇ／ｃｍ３，木材基本密度在地点和无性系间均存在极显著差异．木材基本密度的无性系重复力为０．８２～０．９１，属于受遗传控制较强的材性性状．对生长和材性的相关研究表明，木材基本密度与生长性状（包括胸径、树高和材积）一般存在显著的负相关，但不同地点上表现为不同的正或负的相关关系 相似文献
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长白落叶松种子园优良无性系选择方法研究 总被引：2，自引：0，他引：2
本研究以长白落叶松各子园子代测定结果品质优良、结实量多、种子发芽率高达３项指标为依据，对种子园优良无性系进行选择，共选出优质、高产、品质优良无性系１０个。以方差分析结果为依据，估算出树高、胸径、材积的遗传力分别为０．７２８、０．７１３和０．６８７；遗传增益分别为７．６％、１１．７％和８．２％；材积生长量超过对照６４４．０％，超过各一系均值１３１．１％。这些优良无性系是增产经二代种子园的理想材料，同 相似文献
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１９９２年春于浙江临海进行南方型杨树新无性系引种试验２年。结果其平均胸径达９￣１０ｃｍ，，平均树高达８￣９ｍ，单株材积平均为０．０３￣０．０６ｍ＾３，生长量均比对照增加；各试验中树高、胸径和材积的重复率都比较高，且表现出高度的生长性状遗传相关，无性系之间的主要生长性状差异已十分明显，无性系７２５和１３８８已经具有比其它无性系更明显的超亲优势。 相似文献
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杉木生长,材性兼优种源选择的研究 总被引：4，自引：1，他引：3
经对杉木中心产区优良种源的中间试验研究表明,种源间生长与木材基本密度性状有一定差异,根据对１２年木材基本密度性状和９年材积生长性状的测定结果,初步选出广西那坡,贵州锦屏,贵州榕江等生长,材性兼优的种源。其木材基本密度与广西融水优良种源相近,材积生长比融水种源增加４７．０％￣８３．６％,遗传增益达１３．４１％￣２３．８６％。 相似文献
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杉木无性系生长和木材密度的遗传变异及选择 总被引：3，自引：0，他引：3
研究了８年生杉木无性系试验林的树高、胸径、材积和木材密度的遗传变异规律。结果表明：试验中各性状在无性系间存在显著差异,遗传变异系数树高为９．０％,胸径为１３．７％,材积为３０．０％,而木材密度只有６．７％,各性状均有较高的重复力,木材密度和胸径的重复力在９０．０％以上。树高、胸径、材积３个生长性状间有较高的遗传正相关,而胸径、材 与木材密度间表现出中度的遗传负相关,树高与木材密度间则表现出弱度的遗 相似文献
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通过人工杂交，选育出苏桐３号无性系，生长量显著超过对照兰考桐及苏桐７０无性系，４年生树高、胸径、材积分别比兰考桐增产１０．６％，１６．５％，５６．７％；比苏桐７０无性系增产５．６％，９．２％，３８％。胶合板栽培性状的综合选择指数值分别增加６１．４％和４１．０％。丛枝病发病率与感病指数也显著低于对照。并具有一定的抗风能力。 相似文献
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云南松优树半同胞子代测定 总被引：4，自引：0，他引：4
用４６株云南松优树种子，以优树林分的一般林木种子、商品种子和扭松种子作对照，开展了子代测定，综合评选出优良家系１４个。测算出树高、胸径、材积、直纹株率、木纹理扭转度的遗传力分别为０，６３８１、０．７１９２、０．６６５７、０．７９１０、０．９５２４。用中选的优良家系（入选率３０％）估算遗传增益，材积生长量比亲代群体提高１０％以上，比商品种子子代提高２０％以上；直纹株率比亲代提高８１．１８％，比商品种子提高６４．２６％。云南松的早期选择可在３～５年生时进行。子代的材积生长与亲本无关。 相似文献
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Shaopeng Yin Zhenhai Xiao Guohui Zhao Xin Zhao Xiaoyang Sun Ying Zhang Fuwei Wang Shuchun Li Xiyang Zhao Guan-Zheng Qu 《林业研究》2017,28(4):687-697
The growth traits (tree height, diameter at breast height, and stem straightness degree) and wood properties [wood density (WD), fiber length, fiber width, ash content (AC), lignin content, cellulose content, hemicellulose content (HEC), and holocellulose content] of 208 26-year-old Larix olgensis clones were analyzed. Except for WD and AC, there were significant differences (p < 0.01) for all traits among clones. The phenotypic coefficient of variation and repeatability of all traits were 9.34–35.33% and 0.218–0.930, respectively. Tree height and diameter at breast height showed significant positive correlation; however, the correlation coefficients among growth characteristics and wood properties were mostly not significant. Ten clones (L70, L56, L82, L90, L59, L91, L61, L92, L86, and L64) were selected as excellent clones under a selection rate of 5%, using tree height, diameter at breast height, and stem straightness degree as evaluation indexes, providing genetic gains of 28.69, 17.96, and 0.67%, respectively. Ten clones (L88, L305, L59, L66, L253, L304, L277, L298, L248, and L293) were selected as excellent clones using wood properties as an evaluation index, with a selection rate of 5%, providing genetic gains in WD, fiber length, fiber width, cellulose content, and HEC of 4.14, 3.64, 9.28, 6.77, and 9.61%, respectively. This study provides a theoretical basis for selecting excellent L. olgensis clones. 相似文献
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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
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Early results from three test plantings of Casuarina equisetifolia spp. equisetifolia are reported: a clonal test of 40 locally selected clones, a progeny test of 16 wind-pollinated families of local origin, and a family-in-provenance test of 100 wind-pollinated families which is part of an international provenance trial. All tests were planted in 1996 at the Regional Forest Research Centre, Rajahmundry, Andhra Pradesh, India. Height, stem straightness and axis persistence were measured in the family tests at 6 and 12 months of age. The height of the clonal test was measured at 12 months of age. Heritability estimates obtained were ca. 0.3, 0.2 and 0.1 for height, stem straightness and axis persistence, respectively. Heritability estimates for height were reasonably consistent across the three tests; however, estimates for stem straightness and axis persistence were generally higher in the small test of locally selected families. Height and the other two traits are most probably either weakly correlated or uncorrelated, while stem straightness and axis persistence are positively correlated. Provenances spread across the range of natural- and land-race populations tested demonstrated good growth potential at Rajahmundry. However, natural provenances from Malaysia and Thailand generally showed superior growth, while the land-race populations often demonstrated superior stem straightness. Based on these results some aspects of a breeding strategy are outlined: (a) the establishment of three unrelated sublines; (b) an initial clonal test of all parents; and (c) wind-pollinated mating within clonal breeding orchards. 相似文献
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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
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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
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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