Jiang Ling, Xu Junfeng, Wei Xiangjin, Wang Songfeng, Tang Jiuyou, Zhai Huqu, Wan Jianmin
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Research Center of Jiangsu Plant Gene Engineering, Nanjing Agricultural University, Nanjing 210095, China.
J Genet Genomics. 2007 Jan;34(1):46-55. doi: 10.1016/S1673-8527(07)60006-X.
USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a set of major gene nearly isogenic lines (NIL) and QTL-isogenic lines. The early heading of USSR5 was attributed to the presence of photoperiod-insensitive alleles at E(1) and Se-1 gene, the photoperiod-sensitive inhibitor gene i-Se-1, and the dominant earliness gene Ef-1. Analysis of a backcrossed population (BC(1)F(1)) derived from the cross USSR5 x N22 indicated that two quantitative trait loci (QTL) for early heading were located on chromosomes 7 and 8, accounting for 27.4% and 11.2% of the phenotypic variance, respectively, with both early alleles originating from USSR5. From an F(2) population of the same cross, early heading QTLs were detected on chromosomes 1, 2, 7, 9, and 10, with individual QTL accounting for between 4.1% and 15.4% of the phenotypic variance. Early heading alleles at four of these five QTLs originated from USSR5. A comparison of chromosomal locations suggests that one of these QTLs may be identical with the known gene Hd4 (E(1)). The relationship between the other QTLs and known genes for heading date are not clear. USSR5 is a promising source for propagating earliness for the development of improved early heading rice varieties.
苏联5号是一种来自前苏联的粳稻品种，是极早熟的水稻品种。为了阐明其早熟的遗传基础，通过将其与一组主基因近等基因系（NIL）和QTL近等基因系杂交进行遗传分析。苏联5号的早熟归因于在E(1)和Se-1基因处存在光周期不敏感等位基因、光周期敏感抑制基因i-Se-1以及显性早熟基因Ef-1。对苏联5号与N22杂交产生的回交群体（BC(1)F(1)）的分析表明，两个早熟的数量性状位点（QTL）位于第7和第8染色体上，分别占表型变异的27.4%和11.2%，两个早熟等位基因均来自苏联5号。从同一杂交的F(2)群体中，在第1、2、7、9和10染色体上检测到早熟QTL，单个QTL占表型变异的4.1%至15.4%。这五个QTL中的四个早熟等位基因来自苏联5号。染色体位置的比较表明，这些QTL中的一个可能与已知基因Hd4（E(1)）相同。其他QTL与已知抽穗期基因之间的关系尚不清楚。苏联5号是培育早熟水稻改良品种的一个有前景的早熟基因来源。
