Mohammadi Reza, Mendioro Merlyn S, Diaz Genaleen Q, Gregorio Glenn B, Singh Rakesh K
Plant Breeding, Genetics and Biotechnology Division, International Rice Research Institute, DAPO, Box 7777, Metro Manila, Philippines.
J Genet. 2013 Dec;92(3):433-43. doi: 10.1007/s12041-013-0285-4.
Salinity tolerance in rice is critical at reproductive stage because it ultimately determines grain yield. An F2 mapping population derived from a Sadri/FL478 cross was exposed to saline field conditions (6-8 dS m(-1)) after the active tillering stage to identify reproductive stage specific QTLs for salinity tolerance. Genetic linkage map was constructed using 123 microsatellite markers on 232 F2 progenies. Totally 35 QTLs for 11 traits under salinity stress were detected with LOD > 3, out of which 28 QTLs that explained from 5.9 to 30.0% phenotypic variation were found to be significant based on permutation test. Three major QTL clusters were found on chromosomes 2 (RM423-RM174), 4 (RM551-RM518) and 6 (RM20224-RM528) for multiple traits under salinity stress. Both parental lines contributed additively for QTLs identified for the yield components. A majority of the QTLs detected in our study are reported for the first time for reproductive stage salinity stress. Fine-mapping of selected putative QTLs will be the next step to facilitate marker-assisted backcrossing and to detect useful genes for salinity tolerance at the reproductive stage in rice.
水稻在生殖阶段的耐盐性至关重要，因为它最终决定了谷物产量。一个由Sadri/FL478杂交产生的F2作图群体在有效分蘖期后暴露于盐田条件（6 - 8 dS m(-1)）下，以鉴定生殖阶段耐盐性的特定QTL。使用123个微卫星标记在232个F2后代上构建了遗传连锁图谱。在盐胁迫下，共检测到11个性状的35个QTL，LOD > 3，其中基于排列检验，发现28个解释了5.9%至30.0%表型变异的QTL具有显著性。在染色体2（RM423 - RM174）、4（RM551 - RM518）和6（RM20224 - RM528）上发现了三个主要的QTL簇，与盐胁迫下的多个性状相关。两个亲本系对产量构成因素相关QTL的贡献是累加的。我们研究中检测到的大多数QTL是首次报道与生殖阶段盐胁迫相关。对选定的假定QTL进行精细定位将是下一步，以促进标记辅助回交，并检测水稻生殖阶段耐盐性的有用基因。
