染色体区段置换系(CSSL)对于功能分析和设计目标基因的育种具有重要意义。这里,从in稻恢复系Xihui18中鉴定出一种新型水稻CSSL-Z431为受体,粳稻Huhan3为供体。Z431包含来自Huhan3的六个片段,平均取代长度为2.12Mb。与Xihui18相比,Z431增加了单株(PN)的穗数,并显示出短宽的籽粒。Z431的短宽晶粒是由于颖细胞的长度减少和宽度增加引起的。然后,在Xihui18/Z431的次级F2人群中鉴定出13个QTL。再一次,11个QTL(qPL3,qPN3,qGPP12,qSPP12,qGL3,qGW5,qRLW2,qRLW3,qRLW5,qGWT3,qGWT5-2)通过六个单段置换线(SSSL,S1-S6)在F3中开发。此外,这些SSSL检测到15个QTL(qPN5、qGL1、qGL2、qGL5、qGW1、qGW5-1、qRLW1、qRLW5-2、qGWT1、qGWT2、qYD1、qYD2、qYD3、qYD5、qYD12),而不是在F2群体中被识别。Z431的多个穗由qPN3和qPN5控制。OsIAGLU应该是qPN3的候选基因。Z431的短宽晶粒由qGL3、qGW5等控制。通过DNA测序和qRT-PCR分析,确定了qGL3和qGW5的两个最佳候选基因,分别。此外,D1-D3和T1-T2中不同QTL的金字塔显示出独立的遗传或各种上位效应。所以,有必要了解目标QTL的所有遗传效应,以设计育种。此外,这些二级替代线在一定程度上改善了Xihui18的不足,特别是在S1,S3,S5,D1-D3,T1和T2中增加单株产量。
■在线版本包含补充材料,可在10.1007/s11032-022-01284-x获得。
Chromosome segment substitution line (CSSL) is important for functional analysis and design breeding of target genes. Here, a novel rice CSSL-Z431 was identified from indica restorer line Xihui18 as recipient and japonica Huhan3 as donor. Z431 contained six segments from Huhan3, with average substitution length of 2.12 Mb. Compared with Xihui18, Z431 increased panicle number per plant (PN) and displayed short-wide grains. The short-wide grain of Z431 was caused by decreased length and increased width of glume cell. Then, thirteen QTLs were identified in secondary F2 population from Xihui18/Z431. Again, eleven QTLs (qPL3, qPN3, qGPP12, qSPP12, qGL3, qGW5, qRLW2, qRLW3, qRLW5, qGWT3, qGWT5-2) were validated by six single-segment substitution lines (SSSLs, S1-S6) developed in F3. In addition, fifteen QTLs (qPN5, qGL1, qGL2, qGL5, qGW1, qGW5-1, qRLW1, qRLW5-2, qGWT1, qGWT2, qYD1, qYD2, qYD3, qYD5, qYD12) were detected by these SSSLs, while not be identified in the F2 population. Multiple panicles of Z431 were controlled by qPN3 and qPN5. OsIAGLU should be the candidate gene for qPN3. The short-wide grain of Z431 was controlled by qGL3, qGW5, etc. By DNA sequencing and qRT-PCR analysis, two best candidate genes for qGL3 and qGW5 were identified, respectively. In addition, pyramid of different QTLs in D1-D3 and T1-T2 showed independent inheritance or various epistatic effects. So, it is necessary to understand all genetic effects of target QTLs for designing breeding. Furthermore, these secondary substitution lines improved the deficiencies of Xihui18 to some extent, especially increasing yield per plant in S1, S3, S5, D1-D3, T1, and T2.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s11032-022-01284-x.