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对10个10年生日本落叶松无性系的木材基本密度、管胞参数进行了测定.结果表明:木材基本密度,早、晚材管胞宽度和早材长宽比无性系间差异显著;木材基本密度,早、晚材管胞长度,早晚材管胞宽度和早晚材长宽比径向变异模式相似,即从髓心向外以曲线形式不断增加,有时亦有起伏;早材从髓心向外以近似直线的形式缓慢增加,晚材从髓心向外以曲线形式增加,初期增加幅度较大,到一定年龄后趋于水平变化并略有波动;材质性状与树木年轮间的关系以对数方程、幂函数方程、指数方程拟合效果较好;除了晚材壁腔比和早材壁厚外,其它木材性质的重复力均在0.5以上,受中度或中度以上的遗传制约,按照20%的选择率,长宽比和晚材管胞长能获得较高的遗传增益. 相似文献
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日本落叶松无性系选择的研究 总被引:1,自引:0,他引:1
通过对日本落叶松优良无性系的引种栽培试验,初选出适宜于山西省中山山地发展的6个日本落叶松无性系。经对其遗传力测定,树高和地径的遗传力分别为0.351和0.31;利用性状表现水平分析法对其性状表现进行评估,评估结果由高到低依次为日永8、日永85×长3、日永85×长4C、日永8×长12、日永11和日永85×长13。 相似文献
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以黑龙江省七台河市林业局金沙林场9株人工落叶松2 790个样品数据为例,选择6个常用方程进行非线性回归分析,把拟合精度最高的修正Logistic模型作为微纤丝角基础模型y=b1/[1+ exp(b2x)]+b3,然后,利用S-PLUS软件中的NLME过程,拟合非线性微纤丝角模型.采用AIC、BIC、对数似然值和似然比检验等模型评价统计指标对不同模型的精度进行比较分析.结果表明:当对微纤丝角-年龄关系进行拟合时,b1,b2,b3同时作为混合参数时模型拟合效果最好.把相关性结构包括复合对称结构(CS)、一阶自回归结构AR(1)、一阶移动平均结构MA(1)及一阶自回归与移动平均结构[ARMA(1,1)]加入到微纤丝角最优混合模型中,一阶自回归与移动平均模型[ ARMA(1,1)]显著提高了微纤丝角混合模型的拟合精度.模型检验结果表明:混合模型通过校正随机参数值能提高模型的预测精度.因此,混合模型在应用上不仅能反映总体微纤丝角预测,而且能通过方差协方差结构和误差相关性结构校正随机参数来反映个体微纤丝角差异. 相似文献
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采用安全随机抽样,对青凉山日本落叶松种子园1974年栽植的33个无性系,进行生长、结实和抗病性调查。据调查结果,通过单因素测定对比,共筛选出生长优良无性系、结实优良无性系各18个,抗病优良无性系9个。通过综合因素,采用综合指数法选择,共选出综合优良无性系17个,占无性系总数的51.5%,其中特优性系4个,占12.1%。该项地改良现有种子园,营建高世代种子园,推广普及良种,提供了优良因材料和科学依据 相似文献
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对4个12年生的日本落叶松无性系幼龄材早材单根管胞进行了拉伸实验。结果表明:日本落叶松无性系幼龄材早材单根管胞拉伸弹性模量、拉伸强度和断裂伸长率的均值分别为11.44 GPa、616.59 MPa和6.54%,相应的变异系数为26.97%、26.26%和23.17%。方差分析表明日本落叶松幼龄材早材单根管胞拉伸弹性模量和管胞断裂伸长率在无性系间差异极显著(0.01水平),拉伸强度在无性系间差异不显著;株内早材单根管胞拉伸弹性模量、拉伸强度和管胞断裂伸长率在年轮间差异显著。对日本落叶松无性系幼龄材早材单根管胞拉伸力学性能进行遗传参数估计,单根管胞弹性模量和断裂伸长率的重复力分别是0.79和0.57,属于中度到强度遗传控制,无性系早期选择及材性遗传改良潜力较大。 相似文献
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HUANG Yanhui ZHAO Rongjun FEI Benhua Research Institute of Wood Industry Chinese Academy of Forestry Beijing P.R.China. 《中国林业科技(英文版)》2007,6(3):60-65
Microfibril angle (MFA) in Chinese fir was tested by X-ray diffraction apparatus and calculated by computer software. The results were as follows: MFA was controlled strongly by inheritance, and there was no significant difference in MFA among interspecies, juvenile and mature wood. In the longitudinal, MFA reduces with the height rising from 0 to 5.5 m, especially in the heights from 0 to 1.5 m. The values of MFA are nearly consistence from 1.5 to 7.5 m. The variation range was between 10.82°and 12.57°from 1.5 to 7.5 m, R2 of power equation achieved 0.932 1, and analysis of variance indicated that the variation of MFA was not significant from 1.5 to 7.5 m, The age of the trees had an important influence on MFA, consequently, the difference in MFA was significant among annual rings in radial, which was maximal in near pith and reduced rapidly from the pith to sapwood, and its decline tendency was slow beyond the ninth annual ring. MFA reached minimum value at the 15th annual ring, and the difference reached more than 20° and R^2 of binomial equation achieved 0.755 6. 相似文献
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以5年生36个杂种落叶松家系为材料,测定其树高、胸径生长性状,估算变异系数、遗传力和遗传增益,筛选出优良家系。结果表明:各家系的树高、胸径存在较丰富变异,树高变异系数小于胸径,树高、胸径极显著相关(P<0.01),家系间树高、胸径差异均达极显著差异水平(P<0.01)。以10%的入选率,初选出家系1317、1324、1318、和1327为优良家系,树高平均增益为15.98%,胸径平均增益为29.46%。 相似文献
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In this study,the sample data was based on 2 790 samples of 9 trees from dahurian larch (Larix gmelinii) plantations located in Qitaihe Forest Bureau in Heilongjiang Province.The modified Logistic model y = b1 /[1 + exp(b2 x)]+ b3 was selected to modeling microfibril angle from six models based on nonlinear regression.Then,the logistic model was fitted using nonlinear mixed-effect modeling approach based on NLME of S-PLUS software.Evaluation statistics,such as AIC,BIC, Log Likelihood and Likelihood ratio test were used for model comparisons.The results showed that the Logistic model with parameters b1,b2,b3 as mixed effects showed the best performance.Correlation structures included compound-symmetry structure (CS),first-order autoregressive correlation structure AR(1),moving average correlation structure MA(1) and autoregressive-moving average correlation structure[ARMA(1,1)]were incorprated into the best microfibril angle mixed model.[ARMA(1,1)]significantly improved the precision of mixed model.Validation confirmed that the mixed model with calibration of random parameters could provide more accurate and precise prediction.Therefore,the application of mixed model not only showed the mean trends of microfibril angle,but also showed the individual difference based on variance-covariance structure and correlation structure. 相似文献
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The microfibril angle (MFA) of seven poplar clones was determined using X-ray diffraction technique. MFA was measured for
every growth ring at breast height (1.3 m) for all sample trees, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for
clone I-69, Nanlin-95 and Nanlin-895. A total of 900 samples (chips) were assessed. Significant variation was observed among
poplar clones and growth rings. Mean clonal MFAs at the breast height ranged from 15.2° to 21.0°. MFA at breast height varied
from 7.8° to 28° between growth rings and showed a consistent pith-to-bark trend of declining angles. Disc-average microfibril
angle in poplar clones declines rapidly from 0 to 5.6 m height, after which, it is near constant within tree height. Significant
variation was also observed in disc-average MFA among tree heights. Correlation analysis showed that the correlation between
MFAs from rings 5 to 11 at breast height was significant, while whole-tree values of each growth ring were significantly correlated
with the corresponding MFA at breast height. The results of this study provide some basis for genetic selection of poplar
trees based on wood-quality criteria and for devising appropriate sampling strategies for MFA measurement. 相似文献
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介绍了一种新的测量木材微纤丝角的无损检测技术--近红外光谱分析,并详细阐述了测量时木材样品的选择及制备,测量工作包括X射线衍射和近红外光谱采集、多变量数据分析与模型建立的方法及步骤.证明了近红外光谱分析技术可以用于快速准确地预测木材的微纤丝角. 相似文献