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21.
本文介绍矩形区组方"RBS"设计的基本方法,单个"RBS"设计方差分析的数学模型,处理平均数效应,期望均方分解,遗传力及其遗传变异系数估值,并举例介绍"RBS"在树木育种中的应用。 相似文献
22.
对云南省8个地方栽培木豆群体进行调查,对木豆株高、地径、冠幅、单株荚数、虫荚率、单株粒质量及百粒质量等数量性状变异进行分析,结果表明7个性状不论是群体间还是群体内个体间均存在丰富变异。性状相关性分析表明,单株粒质量与单株荚数呈高度正相关,与株高、地径呈弱正相关。单株荚数、虫荚百分率、百粒质量对产量构成贡献最大,通径系数分别为0.8551、-0.2374、0.1799。若将三个性状相结合,选择单株荚数多、粒大、虫荚少的单株,则后代产量可望有明显增加,有可能育成高产高抗虫性品种。 相似文献
23.
本文报道了按照森林土壤标准物质要求采集的二个土壤样品(碱性土-碱灰性褐土;酸性土-黄红壤)和一个植物样品(杉木叶)的制备过程,粒径2mm的土壤样品采用Y型混样,0.149mm的土壤和0.177mm的植物样品采用高铝瓷球磨制备,土壤样品用高湿灭活,植物样品用^60Co辐射灭活,在二年测定标准样品稳定性和同时进行标准样品中微生物类群和数量的分析。土壤、植物标准样品的均匀性和稳定性采用数理统计方法检验,其结果均达到标准物质要求。 相似文献
24.
不同种皮色木豆蛋白质淀粉含量的研究 总被引:4,自引:1,他引:4
对云南省 8个栽培地、10个种皮色的木豆籽实进行蛋白质及淀粉含量分析测定 ,结果表明 :蛋白质、淀粉含量均与栽培地、种皮色和栽培地×种皮色互作呈极显著差异。不同栽培地的蛋白质、淀粉含量分别为 2 0 .73%~ 2 4 .86 %和 4 8.2 3%~ 54 .2 2 % ;不同种皮色的蛋白质、淀粉含量分别为 2 0 .96 %~ 2 3.96 %和50 .0 2 %~ 53.34 % ;除元谋的淀粉含量为第三类以外 ,其余栽培地和种皮色的蛋白质及淀粉含量均为第二类。各栽培地、种皮色间蛋白质、淀粉含量有一定差异 ,但从总体看 ,仍缺乏高蛋白、高淀粉含量类型。 相似文献
25.
Morphological variance and natural types' division of plus trees ofLarix principis-rupprechtii Mayr.
The phenotypic characteristics of the plus trees ofLarix principis-rupprechtii such as stem form, branch angle, branch/stem ratio, branch density, the crown width, crown length, number of short branch
over 5-cm branch segment in length, and the leaf number of each short branch were investigated in seed orchard in the Changcheng
Mountain, Shaanxi Province. According to the morphological characters, the plus tree clones ofLarix principis-rupprechtii were classified into 4 natural types: the narrow-dense-crown type, wide-dense-crown type, wide-sparse-crown type, and the
narrow-sparse-crown type. The result of the cluster analysis showed there was a very significant difference in tree growth
among the four natural types. While comparing the tree growth of four natural types for the last ten years, it was found that
the performance order of various types from good to bad is as follows: the narrow-dense crown type > the wide-dense crown
type > the wide-sparse crown type > the narrow-sparse crown type. The plus trees of narrow-dense-crown, as a fine type, should
be paid great attention to production and prepared to popularize.
Biography: ZHANG Xin-bo (1956-), male, Senior engineer of Shanxi Academy of Forestry Science and Northern Research Institute of Forestry
of China, Taiyuan 030012, P. R. China
Responsible editor: Chai Ruihai 相似文献
26.
27.
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
28.
简介SPSS软件及其方差分析功能。举例阐述单向分组、两向分组、系统分组及多元数据方差分析的数据录入及分析过程,认为SPSS软件的应用可提高林业科学试验数据统计分析的质量和效率。 相似文献
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30.
Estimates of genetic variance and variance of predicted genetic merits using pedigree or genomic relationship matrices in six Brown Swiss cattle populations for different traits 下载免费PDF全文
A. Loberg J. W. Dürr W.F. Fikse H. Jorjani L. Crooks 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(5):376-385
The amount of variance captured in genetic estimations may depend on whether a pedigree‐based or genomic relationship matrix is used. The purpose of this study was to investigate the genetic variance as well as the variance of predicted genetic merits (PGM) using pedigree‐based or genomic relationship matrices in Brown Swiss cattle. We examined a range of traits in six populations amounting to 173 population‐trait combinations. A main aim was to determine how using different relationship matrices affect variance estimation. We calculated ratios between different types of estimates and analysed the impact of trait heritability and population size. The genetic variances estimated by REML using a genomic relationship matrix were always smaller than the variances that were similarly estimated using a pedigree‐based relationship matrix. The variances from the genomic relationship matrix became closer to estimates from a pedigree relationship matrix as heritability and population size increased. In contrast, variances of predicted genetic merits obtained using a genomic relationship matrix were mostly larger than variances of genetic merit predicted using pedigree‐based relationship matrix. The ratio of the genomic to pedigree‐based PGM variances decreased as heritability and population size rose. The increased variance among predicted genetic merits is important for animal breeding because this is one of the factors influencing genetic progress. 相似文献