Priyadarshi Rahul, Arremsetty Hari P S, Singh Akhilesh K, Khandekar Durga, Ulaganathan Kandasamy, Shenoy Vinay, Sinha Pallavi, Singh Vikas K
International Rice Research Institute, South Asia Hub, Hyderabad, India.
Barwale Foundation Research Centre, Hyderabad, India.
Front Plant Sci. 2018 Jul 20;9:1051. doi: 10.3389/fpls.2018.01051. eCollection 2018.
The degree of heterosis in different hybrid rice varieties is reported to be at the highest in / cross combination, however, there is a problem of sterility and semi-sterility in such inter sub specific hybrids. To overcome this problem, it is essential to develop parental lines having wide compatibility ( ) gene. In this study, a functional marker S5-InDel was used for marker-assisted backcrossing (MABB) to introgress gene from Dular into the genetic background of a widely grown recurrent parent IR 58025B, a maintainer line of wild-abortive (WA) cytoplasmic male sterile line, IR 58025A. Further, a closely linked marker was used for the identification of plants devoid of aroma in backcross population to develop hybrids with no aroma. The stringent phenotypic selection followed by background selection of BCF identified plants with 94.51-98.90% of the recurrent parent genome recovery of lines carrying gene. Subsequently, at 10 promising BCF lines possessing gene with high yielding and long-slender grain type were validated for their maintainer behavior through test crosses with IR 58025A. Also the improved lines showed significantly improved spikelet fertility performance while crossed with and testers in comparison to the original recurrent parent. The improved lines developed in the present study, are being converted to CMS lines through marker-assisted backcross breeding to facilitate precise and improved hybrid breeding program in rice.
据报道，不同杂交水稻品种的杂种优势程度在 / 杂交组合中最高，然而，这种亚种间杂交种存在不育和半不育的问题。为克服这一问题，培育具有广亲和（ ）基因的亲本系至关重要。在本研究中，利用功能标记S5-InDel进行标记辅助回交（MABB），将来自Dular的 基因导入广泛种植的轮回亲本IR 58025B的遗传背景中，IR 58025B是野败（WA）型细胞质雄性不育系IR 58025A的保持系。此外，利用一个紧密连锁的标记对回交群体中无香味的植株进行鉴定，以培育无香味的杂交种。通过对BCF进行严格的表型选择和背景选择，鉴定出携带 基因且轮回亲本基因组恢复率为94.51 - 98.90%的株系。随后，通过与IR 58025A进行测交，对10个具有 基因、高产且粒型细长的有前景的BCF株系的保持性能进行了验证。与原始轮回亲本相比，改良株系与 和 测验种杂交时，小穗育性表现也显著提高。本研究中培育的改良株系正通过标记辅助回交育种转化为CMS系，以促进水稻精确和改良的杂交育种计划。
