Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
Amity Institute of Biotechnology, Amity University, Noida, 201303, India.
Sci Rep. 2020 Sep 4;10(1):13877. doi: 10.1038/s41598-020-70664-0.
Marker assisted backcross breeding was used to transfer Saltol, a major QTL for seedling stage salinity tolerance from the donor FL478 to Pusa Basmati 1509 (PB 1509), a high yielding and early maturing Basmati rice variety. Foreground selection was carried out using three markers namely, AP3206f, RM3412b and RM10793, linked to Saltol. In addition, 105 genome-wide SSR markers polymorphic between FL478 and PB 1509 were used in background selection. Among the BCF near isogenic lines (NILs) developed, recurrent parent genome recovery ranged from 96.67 to 98.57%. Multi-season evaluation identified some of the NILs showing significantly higher yield with grain and cooking quality comparable to PB 1509. All the NILs exhibited tolerance to salinity with significantly higher relative water content, membrane stability index and proline content as compared to PB 1509. The root and shoot concentration of Na, K and Na/K in NILs was at par with FL478 under stress conditions. The gene OsHKT1;5 located in the Saltol region showed higher expression levels under stress indicating its role in conferring salinity tolerance. Salt tolerant NILs of PB 1509 will be useful in stabilizing production in salt affected areas.
利用标记辅助回交育种技术，将耐盐性主效 QTLSaltol 从供体 FL478 转移到高产、早熟的巴斯马蒂水稻品种 Pusa Basmati 1509（PB 1509）中。利用与 Saltol 连锁的三个标记 AP3206f、RM3412b 和 RM10793 进行前景选择。此外，还利用 105 个在 FL478 和 PB 1509 之间多态性的全基因组 SSR 标记进行背景选择。在所开发的近等基因系（NIL）中，轮回亲本基因组回收率在 96.67%到 98.57%之间。多季节评估鉴定出一些 NIL 表现出明显更高的产量，其粒质和烹饪品质与 PB 1509 相当。与 PB 1509 相比，所有 NIL 均表现出对盐胁迫的耐受性，具有更高的相对含水量、膜稳定性指数和脯氨酸含量。在胁迫条件下，NILs 的根和地上部的 Na、K 和 Na/K 浓度与 FL478 相当。位于 Saltol 区域的基因 OsHKT1;5 在胁迫下表现出更高的表达水平，表明其在赋予耐盐性方面的作用。PB 1509 的耐盐 NIL 将有助于稳定盐渍地区的生产。
