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引入贝叶斯理论用以从DNA分子标记的表现型(电泳谱带)推断其基因型(DNA来源)。结果表明,根据标记座位独立贫富而确定的遗传信息不完全标记的基因型概率,与根据邻近的遗传信息完全标记的基因型和有关重组率算得的相应贝叶斯概率,通常都有很大的差异,所以在进行数量性状基因定位和标记辅助选择等工作前前,应当计算每一个体基因组上所有遗传信息不完全座位的有关基因型的贝叶斯概率,文中列出计算未知基因型的贝叶斯概率的详细过程,也讨论了贝叶斯概率的若干推广应用。 相似文献
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Systematic positions of Lamiophlomis and Paraphlomis (Lamiaceae) based on nuclear and chloroplast sequences 总被引:1,自引:0,他引:1
Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer (ITS) and chloroplast rpl16 and trnL-F sequence data using maximum parsimony (MP) and Bayesian methods. and outgroup were sampled. Analyses of both separate In total, 24 species representing six genera of the ingroup and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion ofLamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence. 相似文献
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The phylogeny of Ptychostomum was first spacer (ITS) region of the nuclear ribosomal (nr) DNA DNA rps4 sequences. Maximum parsimony, maximum undertaken based on analysis of the internal transcribed and by combining data from nrDNA ITS and chloroplast likelihood, and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not monophyletic. Ptychostomum funkii (Schwagr.) J. R. Spence (≡ Bryum funkii Schwaigr.) is placed within a clade containing the type species of Bryum, B. argenteum Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular analyses. On the basis of phylogenetic evidence, we agree with transferring B. amblyodon Mull. Hal. (≡ B. inclinatum (Brid.) Turton≡ Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mull. Hal., Bryum pallescens Schleich. ex Schwaigr., and Bryum pallens Sw. to Ptychostomum. 相似文献
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多水平贝叶斯模型预测森林土壤全氮 总被引:1,自引:0,他引:1
多水平贝叶斯方法阐明了预测中观测值、模型和参数的不确定性,被越来越多的生态学家所使用.应用多水平贝叶斯方法建立了北京八达岭地区森林土壤全氮模型,分析了模型参数及其不确定性,并对该区不同土壤层(A、B、C)全氮含量进行了预测.得到如下结论:(1)该区森林土壤全氮多水平贝叶斯模型为yi~N(β0j[i],k[j]+β1j[i],k[j]xi,σ2y).(2)对模型参数和其曲线不确定性分析表明,该模型能够很好的预测该区土壤全氮含量.(3)模型预测表明:土壤A层,随着海拔的增加,全氮含量递增.土壤B层,随着海拔的升高,植被类型0、1、2、3土壤全氮含量递增,而植被类型4土壤全氮含量出现递减现象.土壤C层,随着海拔的增加,植被类型0土壤全氮含量递增,而植被类型1、2、3、4土壤全氮含量均表现为递减.各植被类型土壤全氮含量都随着土层的深度而减少. 相似文献
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针对当前虫生真菌研究过程中存在的一些昆虫学问题,文章从虫草Cordyceps sensu lato和虫霉Entomophthorales这两类虫生真菌出发,对物种名称的规范、虫生真菌的发生与寄主昆虫生物学之间的关系以及寄主昆虫的鉴定等方面展开讨论,并提出解决方案和推论,旨在深入了解虫生真菌的一些生物学问题。 相似文献
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准确预测土壤有机碳的空间分布,对于土壤资源开发和保护、应对气候变化和生态系统健康都具有重要意义.本文以塔里木盆地北缘盐土1300 m×1700 m样地为试验区,采集5~10 cm深度土壤样品144个,构建土壤有机碳含量的贝叶斯地统计空间预测模型,并以普通克里格、序惯高斯模拟和逆距离加权方法为对照,评价贝叶斯地统计对土壤有机碳含量的预测性能.结果表明: 研究区土壤有机碳含量处于1.59~9.30 g·kg-1,平均值为4.36 g·kg-1,标准偏差为1.62 g·kg-1;半方差函数符合指数模型,空间结构比参数值为0.57;利用贝叶斯地统计方法,获得了土壤有机碳含量的空间分布图以及评价预测不确定性的预测方差、上95%分位数、下95%分位数分布图;与普通克里格、序惯高斯模拟和逆距离加权方法相比,贝叶斯地统计方法具有更高的土壤有机碳含量空间预测精度,显示出该方法对土壤有机碳含量预测的优越性. 相似文献
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应用贝叶斯理论推断DNA分子标记基因型 总被引:4,自引:0,他引:4
引入贝叶斯理论用以从DNA分子标记的表现型(电泳谱带)推断其基因型(DNA来源)。结果表明,根据标记座位独立贫富而确定的遗传信息不完全标记的基因型概率,与根据令近的遗传信息完全标记的基因型和有关重组率算得的相应贝叶斯概率,通常都有很大的差异,所以在进行数量性状基因定位和标记辅助选择等工作之前,应当计算每一个体基因组上所有遗传信息不完全座位的有关基因型的贝叶斯概率。文中列出计算未知基因型的贝叶期概率的详细过程,也讨论了贝叶斯概率的若干推广应用。 相似文献