Intergenomic recombination in F1 lily hybrids (Lilium) and its significance for genetic variation in the B1 progenies as revealed by GISH and FISH
Intergenomic recombination in F1 lily hybrids (Lilium) and its significance for genetic variation in the B1 progenies as revealed by GISH and FISH
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DOI：
10.1139/g05-057
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发表时间：
2005-10-01
期刊：
影响因子：
3.1
通讯作者：
Van Tuyl, JM
中科院分区：
文献类型：
--
作者：
Barba-Gonzalez, R;Ramanna, MS;Van Tuyl, JM
在与亚洲亲本回交的东方（O）x亚洲（A）百合（百合）的BC群体中评估基因组间重组。该群体由来自东方×亚洲百合（2n = 2x = 24）的二倍体F-1的2个基因型（951502-1和952400-1）的2n配子产生的38个植株组成。在大多数公元前，植物，有证据表明，第一次分裂恢复，有或没有交叉，导致功能配子。然而，有5个BC，其中2n配子起源于不确定减数分裂恢复（IMR）。根据特定同源染色体对的重组染色体数目，鉴定了3种类型的植物：（i）既具有交换的互反产物，（O/A，A/O，其中O代表O基因组的着丝粒，A代表亚洲染色体的重组片段，反之亦然）;（ii）具有O基因组的1条正常染色体和1条重组染色体（O，A/O）的那些;和（iii）具有A基因组的1条正常染色体和重组染色体（A，O/A）的那些。A × OA回交后代的一个重要特征是在重组染色体O/A存在的任何地方发生交换远端区段的置换。在IMR的情况下，近端和远端重组片段都发生了替换。这些取代的重要性在于它们提供了在多倍体中隐性基因的表型表达的可能性（即，nuliplex基因型）。
Intergenomic recombination was assessed in a BC, population of Oriental (O) x Asiatic (A) lilies (Lilium) backcrossed to Asiatic parents. This population consisted of 38 plants generated from the 2n gametes from 2 genotypes (951502-1 and 952400-1) of the diploid F-1, Oriental x Asiatic lilies (2n = 2x = 24) as parents. In the majority of BC, plants, there was evidence that first division restitution, with and without crossovers, resulted in functional gametes. However, there were 5 BC, plants in which 2n gametes originated from indeterminate meiotic restitution (IMR). Based on the number of recombinant chromosomes for a particular homoeologous pair, 3 types of plants were identified: (i) those with both the reciprocal product of a crossover (O/A, A/O, where O represents the centromere of the O genome and A the recombinant segment of Asiatic chromosome, and vice versa); (ii) those with 1 normal chromosome of the O genome and a recombinant chromosome (O, A/O); and (iii) those with 1 normal chromosome of the A genome and a recombinant chromosome (A, O/A). An important feature of A x OA backcross progeny is the occurrence of substitutions for the segment distal in the crossover wherever the recombinant chromosome O/A was present. In the case of IMR, the substitution occurred for both proximal and distal recombinant segments. The significance of these substitutions is that they offer the potential for the phenotypic expression of recessive genes in polyploids (i.e., nulliplex genotype).