JOINT SELECTION FOR BOTH EXTREMES OF MEAN PERFORMANCE AND OF SENSITIVITY TO A MACRO-ENVIRONMENTAL VARIABLE .1. FAMILY SELECTION
JOINT SELECTION FOR BOTH EXTREMES OF MEAN PERFORMANCE AND OF SENSITIVITY TO A MACRO-ENVIRONMENTAL VARIABLE .1. FAMILY SELECTION
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DOI：
10.1038/hdy.1977.27
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发表时间：
1977-01-01
期刊：
影响因子：
3.8
通讯作者：
JINKS, JL
中科院分区：
文献类型：
--
作者：
BRUMPTON, RJ;BOUGHEY, H;JINKS, JL
尽管平均表现和对宏观环境变量的敏感性之间存在高度相关性，但越来越多的证据表明，它们至少在一定程度上受到独立的遗传控制。从分离这两个表型方面的2个纯育种系之间的杂交中，应该可以选择显示出高和低性能与高和低灵敏度的所有4种可能组合的重组体。通过在黄花烟草品种2和12之间的杂交F3中开始的2个周期的选择来测试该预测，以获得2个性状（开花时间和最终高度）的平均表现和环境敏感性。选择是在家庭的基础上，播种日期是宏观环境变量。在质量上，4个组合中的3个开花时间和3个最终高度符合F5的选择标准。从数量上看，所有的选择都没有达到如果性能和灵敏度的所有遗传变异都可独立用于选择时所能达到的水平。敏感性的实现遗传力仅为性能的一半。人们曾期望，通过单粒种子遗传，从同一杂交产生的近交系中进行选择会更成功，但这种期望正在受到考验。
In spite of the frequency with which mean performance and sensitivity to macro-environmental variables are highly correlated, there is a growing body of evidence that they are, at least in part, under independent genetical control. From a cross between 2 pure breeding lines which segregate for both of these aspects of the phenotype, it should be possible to select recombinants which display all 4 possible combinations of high and low performance with high and low sensitivity. This prediction was tested by 2 cycles of selection initiated in the F3 of a cross between varieties 2 and 12 of Nicotiana rustica for the mean performance and environmental sensitivity of 2 characters, flowering time and final height. Selection was on a family basis, date of sowing being the macro-environmental variable. Qualitatively, 3 of the 4 combinations for flowering time and 3 of the 4 for final height met the selection criteria by the F5. Quantitatively, all selections fell short of what could have been achieved if all the genetical variation in performance and sensitivity was independently available for selection. The realized heritability for sensitivity was only half that for performance. The expectation that selection among inbreds produced from the same cross by single seed descent would be more successful is being tested.