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川西云杉分布于四川西部,西藏东部及南部,青海南部,是重要的速生用材树种。本文对引种的6年生川西云杉和乡土树种青海云杉、青杄年生幼林的生长及形态性状进行连续6a的综合研究,以进一步验证川西云杉的生长优势的进行早期评价,研究表明,6年生川西云杉与青海云杉、青杄的树高、地径、新梢长、分枝角度、一级侧枝、顶轮侧枝、顶轮侧枝总长、针叶干鲜重大都存在极显著的差异,苗高达到73.6cm,比青海云杉、青杄的生长量分别提高了36.9%和23.3%,在我国甘肃天水地区生长表现良好,适应性强,稳定性高的优良云杉种。 相似文献
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《绿色科技》2016,(11)
利用欧洲云杉(Picea abies)优良种源超级苗采穗圃的2816个优良单株进行了扦插无性系化,采用强化培育技术对无性系苗培育2a后,调查观测了各个无性系苗高、地径、新梢长、侧枝数及保存率。利用标准差法,从该批无性系中经过两次选择出优良无性系175个;进行下一步无性系评价,并通过多阶段选择,达到了选出优良无性系的目的。2013年3月在湖北宜昌国有樟村坪林场营造欧洲云杉优良无性系175个田间试验林,根据5年(苗龄2年)保存率和生长量,再次选择出欧洲云杉13个优良无性系,试验结果表明:现实增益5年生平均树高比其它162个平均树高提高24.3%,当年抽梢提高40.4%,地径提高27.3%,冠幅提高18.3%,顶轮分枝数提高25%,保存率提高53.1%。比神农架(CK)大果青扦平均树高提高10.6%。与甘肃省小陇山优良无性系生长量结果相吻合。 相似文献
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《林业勘察设计》2018,(3)
采用双因素随机区组试验设计,在福建沙县进行杉木林下套种闽楠试验,分析生境与容器苗选择对闽楠生长的影响,结果表明:林窗较林冠下生境能显著促进闽楠幼树的树高、地径、冠幅、当年抽梢的生长,显著增加闽楠幼树的一级侧枝数量、一级侧枝长度、抽梢一级侧枝数量、抽梢一级侧枝密度,树冠圆满度显著变小;采用2年生容器大苗造林较常规1年生容器苗造林可显著提高闽楠幼树的树高、地径、冠幅、当年抽梢,增加闽楠幼树的一级侧枝数量、一级侧枝密度、一级侧枝均长、抽梢一级侧枝数量、抽梢一级侧枝密度,但树冠圆满度变小;容器苗因素在闽楠幼树生长和树冠特征因子方面影响作用大于生境因素,两个因素仅在抽梢1级侧枝数量方面存在着极显著性交互作用。应用容器大苗造林法,创造林窗生境和在林窗生境栽植是提高林下闽楠更新层培育成效的关键技术。 相似文献
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桉树优良无性系工厂化育苗技术 总被引:2,自引:0,他引:2
从桉树优良无性系工厂化育苗的生产流程入手,系统地介绍了桉树优良无性系组培苗的培育和以组培苗营养袋苗为母株,建立采穗圃,培育大量插条用以生产扦插苗的技术。其间以尾巨桉EF7为例,插入组培苗芽增殖培养基选择,促进生根培养基的选择,以及扦插条激素处理选择等的试验方法及过程,以加强桉树优良无性系工厂化育苗技术体系的力度。 相似文献
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对2~5年生马尾松实生苗、扦插苗2种苗木进行造林对比试验,试验结果显示,这2种苗木造林的保存率都超过95%。扦插苗和实生苗2年生时5个测量性状(树高、胸径、冠幅、活枝轮盘数、侧枝总数)均差异不显著;3年生时树高、胸径差异显著,其它不显著;4年生时5个性状差异均显著。即从3年生开始扦插苗早期生长量才显著高于实生苗。说明扦插林早期较实生林速生。在种子短缺的情况下,利用优良的无性系繁殖苗木,是十分有效的。 相似文献
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对8a生泡桐林分的连续测定结果表明:丛枝病对泡桐新无性系的生长有一定影响,但只有在主梢发病、一级侧枝多数发病或少数一级侧枝呈大片丛状时才显著受到抑制;试样群体无性系间的生长差异大于不同感病级泡桐的生长差异。 相似文献
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对引进的欧洲云杉、西加云杉、白云杉、黑云杉以及国内的川西云杉和青海云杉的24个不同种和种源生长及分枝性状进行早期(8年生)测定与评价.结果表明:5年生长期内生长及形态性状在不同的云杉种间和种源间的差异多数达到极显著或显著水平,且种和种源的方差分量分别占总方差分量的32.47%和23.97%,证明不同种间和种源间存在较大的遗传变异.通过多重比较和相关分析发现,国外的云杉种较国内种在生长表现和适应性上均有明显的优势.经性状相关分析得知:各个生长及形态性状之间均存在极显著的正相关关系,尤其是苗高与各分枝性状之间的相关系数均值为0.825 9.最后利用苗高为主要指标初步筛选出6个优良种源,人选的种源均表现出明显的优势,其中苗高、侧枝总数以及当年侧枝数的平均值分别为117.07 cm、57.75、12.46,均分别比对照种源的总平均值高48.54%、56.46%和63.30%. 相似文献
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对5年生和7年生青海云杉苗进行了不同方式的修剪,同时用不同的生长调节剂对其主干和侧枝上的芽进行了处理,发现除去青海云杉顶芽,能够促进苗木侧芽和隐芽的生长发育,提高侧芽的抽枝率,增加新枝的生长量.不同种类的生长调节剂和修剪方式对青海云杉芽的生长发育影响效果显著不同,去顶芽修剪的效果优于纺锤形修剪和篱式修剪,对于7年生苗,主干上仅留3个饱满芽的强度修剪能明显地减少主干上的芽数,使抽枝数也随之减少,处理效果最差.去顶芽能够明显的增加当年新梢数量和长于6 cm的新梢总长度,同时还能增加当年新梢上冬芽数.6BA对青海云杉芽和枝条的生长发育有较好的促进作用,抽枝宝在各个修剪处理中表现均最差,甚至在一定程度上抑制了青海云杉芽的萌发和延长生长.修剪和生长调节剂处理对5年生苗侧枝芽抽枝数影响均极显著,而对7年生苗的影响却不显著;修剪和生长调节剂的交互作用明显地影响了对7年生苗的处理效果,而对5年生苗的影响不显著.去顶芽后再用6BA涂抹青海云杉苗上的保留芽,能有效地促进青海云杉保留芽的生长发育,有利于形成更多枝条,对青海云杉采穗圃苗的处理效果最佳,强度修剪和用抽枝宝抹芽不适于青海云杉采穗圃苗的培育. 相似文献
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为揭示不同区域核桃优树无性系1年生嫁接苗生长及变异规律,为区域核桃种资源筛选及开发提供参考依据,以云南省昭通市21个核桃优树无性系为试验材料,对其1年生嫁接苗苗高、地径进行遗传变异分析、方差分析、Pearson相关性检验、聚类分析及苗木分级评价,并对无性系母树环境因子进行主成分分析。结果表明,各核桃优树无性系1年生嫁接苗平均苗高范围为6~162 cm,变幅为29.95~80.20 cm,平均值为53.06 cm,变异系数总体为49.09%,变幅为34.61%~68.76%;平均地径0.6~3.0 cm,变幅为1.053~1.662 cm,平均值为1.298 cm,变异系数总体为29.13%,变幅为19.24%~35.44%。各核桃优树无性系间苗高和地径差异均达到极显著水平,苗高和地径的均值均呈极显著正相关。核桃优树无性系受地理位置影响最明显,其次是年降水量、年温度。地径对区域核桃良种资源的选择贡献较小,苗高可作为区域核桃良种资源早期初步筛选的主要参数。 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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Clonal variations in cone,seed and nut traits in a Pinus koraiensis seed orchard in Northeast China 总被引:1,自引:0,他引:1
《林业研究》2021,32(1)
Korean pine(Pinus koraiensis Siebold Zucc.)in Northeastern China has been genetically improved to increase seed yields in addition to timber.To assess seed yield variability and select highly productive clones,14 cone,seed and nut traits were measured and analyzed.Variance analysis showed that all clones were significantly different in various traits(P0.01).Phenotypic coefficients of variation and repeatability of traits ranged from 9.1 to34.4% and from 27.5 to 97.7%,respectively.Except for the cone layer and cone seed numbers,the other traits were positively or negatively correlated.Three principal components were identified.Seed and nut traits were the most important traits in the first principal component,and cone traits more important in the second.Using correlation and principal component analyses,cone number and other traits were selected to evaluate materials.Twenty-two clones were selected using a selection rate of 10% based on cone number independently or other combined traits.The genetic gain for different traits ranged from 6.2 to 24.3%.The selected elite clones can supply seedlings for reforestation and the selection method can provide a theoretical basis for selection in other conifer species. 相似文献
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Bud-burst on first order lateral branches of Abies bafsamea L. (balsam fir) was delayed when the branches were rotated 180 degrees about their long axis. This was not a consequence of injury caused by the treatment because buds rotated 180 degrees on inverted plants flushed at the same time as the controls, whereas flushing of all other buds was delayed. Buds thus appear to be more vigorous when maintained in the same orientation to gravity in which they are formed and the site of gravitational stimulus perception appears to be the bud itself. Except on the leading shoot, leaves from inverted buds turned so that their adaxial surface faced upward, unless there was intense illumination from below. However, both anisophylly and positioning of leaves on lateral shoots were apparently predetermined because the shorter, more forward pointing leaves appeared below the longer distichous leaves on shoots from inverted buds. Shoots with normally oriented leaves appeared the next season. 相似文献
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From four Korean pine (Pinus koraiensis) orchards, 60 clones were selected and analyzed for the fatty acid and amino acid components of the seeds to reveal the variations and correlations of the seed characteristics among the clonal source orchards and clones. The nutritional components of the seeds of the P. koraiensis trees exhibited rich genetic variation; the variation coefficient of the fatty acids was 2.24–66.83 %, while the variation coefficient of the amino acids was 14.70–38.88 %. Relatively high genetic-improvement potential exists for the nutritional components of the seeds. The phenotypic differentiation of the fatty acid and amino acid components reveals that variation within the population (85.18 %) was the primary source for the variation of the fatty acid components; variation among the orchards (63.08 %) was the primary source of the variation of the amino acid components. Data drawn from various clonal source orchards all showed that the seed characteristics were highly controlled by heritability (h2 > 80 %), and the seed characteristics of the P. koraiensis trees exhibited a similar genetic gain trend. The principal components were analyzed to obtain the comprehensive principal component value for each clonal seed orchard. Twelve clones were selected based on a clonal selection rate of 20 %. Correlation and multiple stepwise-regression analyses were conducted, considering different location conditions, to reveal the stable correlations between the seed characteristics to facilitate improvements of the seed yield of P. koraiensis trees and the clonal selection. Species of real characteristics in P. koraiensis were controlled by higher heritability. Genetic gain was obtained by selecting of superior clones. 相似文献
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该文报道了大叶榉树无性系2年生幼林生长测定结果。研究表明,不同无性系树高、胸径、枝下高、冠幅、干形、分枝数、分枝粗、分枝角度等8个性状均有显著差异(P0.05),不同性状的遗传变异系数在4.7%~26.6%之间,性状重复力在0.49~0.89之间。胸径与树高、枝下高之间,冠幅与分枝角度、干形(弯曲度)之间存在显著正相关,树高与分枝粗度之间存在显著的负相关。主成分分析结果显示,无性系性状前4个主成分的贡献率达85.21%,利用主成分得分值进行聚类分析,可将24个无性系划分为4类。以用材为育种目标,初选出"红4"、"桔3"和"黄10"等3个优良无性系。 相似文献