Crop Science Research Laboratory, USDA-ARS, 810 Highway 12 East, Mississippi State, MS 39762-5367, USA.
Theor Appl Genet. 2010 Apr;120(6):1193-205. doi: 10.1007/s00122-009-1247-3. Epub 2010 Jan 23.
We recently released a set of 17 chromosome substitution (CS-B) lines (2n = 52) that contain Gossypium barbadense L. doubled-haploid line '3-79' germplasm systematically introgressed into the Upland inbred 'TM-1' of G. hirsutum (L.). TM-1 yields much more than 3-79, but cotton from the latter has superior fiber properties. To explore the use of these quasi-isogenic lines in studying gene interactions, we created a partial diallel among six CS-B lines and the inbred TM-1, and characterized their descendents for lint percentage, boll weight, seedcotton yield and lint yield across four environments. Phenotypic data on the traits were analyzed according to the ADAA genetic model to detect significant additive, dominance, and additive-by-additive epistasis effects at the chromosome and chromosome-by-chromosome levels of CS-B lines. For example, line 3-79 had the lowest boll weight, seedcotton yield and lint yield, but CS-B22Lo homozygous dominance genetic effects on seedcotton and lint yield were nearly four times those of TM-1, and its hybrids with TM-1 had the highest additive-by-additive epistatic effects on seedcotton and lint yield. CS-B14sh, 17, 22Lo and 25 produced positive homozygous dominance effects on lint yield, whereas doubly heterozygous combinations of CS-B14sh with CS-B17, 22Lo and 25 produced negative dominance effects, suggesting that epistatic effects between genes in these chromosomes strongly affect lint yield. The results underscore the opportunities to systematically identify genomic regions harboring genes that impart agronomically significant effects via epistatic interactions. The chromosome-by-chromosome approach significantly complements other strategies to detect and quantify epistatic interaction effects, and the quasi-isogenic nature of families and lines from CS-B intermatings will facilitate high-resolution localization, development of markers for selection and map-assisted identification of genes involved in strong epistatic effects.
我们最近发布了一组 17 条染色体替换（CS-B）系（2n=52），这些系包含系统渐渗有海岛棉双倍体品系 '3-79' 遗传物质的陆地棉自交系 'TM-1'。TM-1 的产量远高于 '3-79'，但后者的棉花纤维性能更好。为了探索这些准同基因系在研究基因互作中的应用，我们在六个 CS-B 系和自交系 TM-1 之间创建了一个部分双列杂交，并在四个环境中对其后代的皮棉百分率、铃重、籽棉产量和皮棉产量进行了表型分析。根据 ADAA 遗传模型分析了这些性状的表型数据，以检测 CS-B 系的染色体和染色体间水平上的显著加性、显性和加性-显性上位性效应。例如，系 3-79 的铃重、籽棉产量和皮棉产量最低，但 CS-B22Lo 纯合显性遗传效应对籽棉和皮棉产量的影响几乎是 TM-1 的四倍，其与 TM-1 的杂种对籽棉和皮棉产量的加性-显性上位性效应最高。CS-B14sh、17、22Lo 和 25 对皮棉产量产生了正纯合显性效应，而 CS-B14sh 与 CS-B17、22Lo 和 25 的双杂合组合对皮棉产量产生了负显性效应，这表明这些染色体上基因之间的上位性效应强烈影响皮棉产量。这些结果突出了通过上位性互作系统地鉴定赋予农艺重要影响的基因组区域的机会。染色体间方法显著补充了其他检测和量化上位性互作效应的策略，CS-B 互交系的准同基因性质将有助于进行高分辨率定位、开发选择标记和图谱辅助鉴定涉及强上位性效应的基因。
