Retrospective selection of elite parent trees using paternity testing with microsatellite markers:: an alternative short term breeding tactic for Eucalyptus
Retrospective selection of elite parent trees using paternity testing with microsatellite markers:: an alternative short term breeding tactic for Eucalyptus
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DOI：
10.1007/s00122-004-1617-9
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发表时间：
2004-06-01
影响因子：
5.4
通讯作者：
Rezende, GDSP
中科院分区：
文献类型：
--
作者：
Grattapaglia, D;Ribeiro, VJ;Rezende, GDSP
在古老的林木种子园中进行改良的传统方法是建立包括每棵亲本树的子代试验，然后通过估计其一般和特殊配合力（GCA和SCA）来评估其对子代表现的贡献。以巨桉种子园为研究对象，采用单亲本和6个桉树种子园建立的杂交种子果园，通过对杂交种子园的上级后代进行亲子鉴定，成功地应用了一种替代亲本选择策略。尾叶花粉亲本一组14个微卫星标记被用来进行亲子关系测试的256个后代个体，包括两个独立的样本选择的树木和一个控制的样本，所有来自6岁的森林在巴西东部的立场。亲子鉴定进行了一个连续的亲子排除程序的所有后代个体。仅当后代树中的专性父本等位基因不存在于声称的亲本树中至少四个独立标记时才宣布排除，以避免由于突变或无效等位基因而导致的错误排除。在进行母体检查以确定种子混合物和自交个体后，亲子鉴定显示，大约29%的后代是由果园外的花粉父母产生的。在所选样品中未发现自交后代。三个花粉父母被发现有父系的选择和非选择的后代个体的样本中的基本上所有的后代。这三个亲本中有一个亲本的选择后代数显著高于其他亲本（Fisher精确检验P <0.0002）。根据这些结果，低繁殖成功的父母被淘汰出果园，并采取管理程序，以尽量减少外部花粉污染。差异有显著性（P
The conventional way to drive modifications in old forest tree seed orchards is to establish progeny trials involving each parent tree and then evaluate its contribution to the performance of the progeny by estimating its general and specific combining ability (GCA and SCA). In this work, we successfully applied an alternative parent selection tactic based on paternity testing of superior offspring derived from a hybrid seed orchard established with a single Eucalyptus grandis seed parents and six E. urophylla pollen parents. A battery of 14 microsatellite markers was used to carry out parentage tests of 256 progeny individuals including two independent samples of selected trees and one control unselected sample, all derived from 6-year-old forest stands in eastern Brazil. Paternity determination was carried out for all progeny individuals by a sequential paternity exclusion procedure. Exclusion was declared only when the obligatory paternal allele in the progeny tree was not present in the alleged parent tree for at least four independent markers to avoid false exclusions due to mutation or null alleles. After maternity checks to identify seed mixtures and selfed individuals, the paternity tests revealed that approximately 29% of the offspring was sired by pollen parents outside the orchard. No selfed progeny were found in the selected samples. Three pollen parents were found to have sired essentially all of the offspring in the samples of selected and non-selected progeny individuals. One of these three parents sired significantly more selected progeny than unselected ones (Pless than or equal to0.0002 in a Fisher exact test). Based on these results, low-reproductive-successful parents were culled from the orchard, and management procedures were adopted to minimize external pollen contamination. A significant difference (P