THE SEMIDWARF GENE, SD-1, OF RICE (ORYZA-SATIVA L) .2. MOLECULAR MAPPING AND MARKER-ASSISTED SELECTION
THE SEMIDWARF GENE, SD-1, OF RICE (ORYZA-SATIVA L) .2. MOLECULAR MAPPING AND MARKER-ASSISTED SELECTION
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DOI：
10.1007/bf00226982
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发表时间：
1994-09-01
影响因子：
5.4
通讯作者：
CHAE, YA
中科院分区：
文献类型：
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作者：
CHO, YG;EUN, MY;CHAE, YA
为了确定半矮秆基因SD-1、花青素激活剂(A)、紫色节(Pn)、紫色耳廓(PAU)和同工酶ESTI-2与DNA标记在水稻分子连锁图谱上的位置，20个RFLP标记以前被定位在1号染色体的中心区(McCouch等人)。1988)，定位于杂交组合台中65(A、Pla、Pau)/台中65(SD-1)的F-2群体。SD-1和ESTI-2与RFLP标记RG 109和RG 220连锁最紧密，RG 109和RG 220相互共分离。根据观察到的0.8%的重组值，估计这些RFLP标记与sn-1之间的距离为0.8 cM。1号染色体该区域的基因和标记顺序为SD-1(ESTI-2-RG220-RG109)-RG381-A-PN-PAU。为了验证利用这些连锁标记对SD-1进行选择的效果，对来自另一个杂交组合密阳23/Gihobyeo的50d龄的F-2幼苗进行了标记基因分析。在这个年龄段，根据表型还不能很清楚地检测出半矮秆性状。此外，株高在该种群中呈正态分布，因此很难明确识别携带SD-1的植物。在ESTI-2、RG220和RG109上选择了13株SD-1相关等位基因纯合的幼苗，在所有3个标记座位上选择了13株SD-1相关等位基因纯合的幼苗进行了进一步的遗传分析。在抽穗后20天，对26株植株进行了茎长测量，每一株都确认了预期的表型。然后对这26个植株进行4个世代的自交，并再次对FG系进行评估，以确定是否可以检测到这三个分子标记之间或这些标记与SD-1基因之间的任何重组。没有鉴定出重组子，这证实了这些座位的紧密连锁，以及在根据表型进行评估之前对该隐性半矮秆性状进行基因选择的有效性。
To establish the location of the semidwarf gene, sd-1, the anthocyanin activator (A), purple node (Pn), purple auricle (Pau), and the isozyme locus, EstI-2, in relation to DNA markers on the molecular linkage map of rice, 20 RFLP markers, previously mapped to the central region of chromosome 1 (McCouch et al. 1988), were mapped onto an F-2 population derived from the cross Taichung 65 (A, Pla, Pau)/Taichung 65 (sd-1). sd-1 and EstI-2 were determined to be linked most tightly to RFLP markers RG 109 and RG 220, which cosegregated with each other. The distance between these RFLP markers and sn-1 was estimated to be 0.8 cM, based on an observed recombination value of 0.8%. The order of genes and markers in this region of chromosome 1 was determined to be sd-1 (EstI-2 - RG220 - RG109) - RG381 - A - Pn - Pau. To test the efficacy of selection for sd-1 based on these linked markers, 50-day-old F-2 seedlings derived from another cross, Milyang 23/Gihobyeo, were analyzed for marker genotype. At this age, the semidwarf character could not be clearly detected based on phenotype. In addition, plant height was normally distributed in this population, making it difficult to unambiguously identify plants carrying sd-1. Thirteen seedlings homozygous for the sd-1-associated allele at EstI-2, RG220 and RG109, and 13 seedlings homozygous for the Sd-1-associated allele at all three marker loci were selected for further genetic analysis. At 20 days after heading, the culm lengths of these 26 plants were measured and the expected phenotype was confirmed in every case. These 26 plants were then selfed for four generations and Fg lines were again evaluated to determine whether any recombination among the three molecular markers, or between these markers and the sd-1 gene, could be detected. No recombinants were identified, confirming the tight linkage of these loci and the usefulness of genotypic selection for this recessive semidwarf character prior to the time when it can be evaluated based on phenotype.