Department of Agronomy, University of Kentucky, 40546, Lexington, KY, USA.
Theor Appl Genet. 1993 Jun;86(5):557-61. doi: 10.1007/BF00838708.
Theory predicts that selection for adaptability during the short term also favors selection for a reduced recombination rate in the population. The objective of this study was to test whether the cyclic short-term selection which has taken place in soybean breeding programs in the USA since the introduction of the crop has measurably reduced recombination frequencies. Thirteen soybean varieties separated into four different release periods (prior to 1940, 1940-1954, 1955-1969, after 1970) were evaluated for their recombination frequencies within three locus pairs. Recombination frequencies among the individual varieties ranged from 7.6 to 24.1 % at thep 1 r locus pair, from 20.9 to 30.1 % at thelnp 2 locus pair, and from 28.7 to 41.6% at thedt 1 l 1 locus pair. Recombination frequencies were significantly different among varieties within a release period for thep 1 r andlnp 2 locus pairs, but recombination frequencies did not differ among release periods for any locus pair. Thus, apparently, plant breeders have developed soybean varieties with improved adaptation without influencing recombination rates.
理论预测，在短期内选择适应性也有利于选择降低种群中的重组率。本研究的目的是检验自作物引入美国以来，大豆育种计划中发生的周期性短期选择是否显著降低了重组频率。13 个大豆品种分为四个不同的释放期（1940 年前、1940-1954 年、1955-1969 年、1970 年后），在三个基因座对中评估其重组频率。个体品种之间的重组频率在 p1r 基因座对中为 7.6%至 24.1%，在 lnp2 基因座对中为 20.9%至 30.1%，在 dt1l1 基因座对中为 28.7%至 41.6%。在 p1r 和 lnp2 基因座对中，同一释放期内品种间的重组频率存在显著差异，但任何基因座对的释放期之间的重组频率均无差异。因此，显然，植物育种家已经开发出了具有更好适应性的大豆品种，而没有影响重组率。
