Abstract:
Rice grain size is a key determinant of both grain yield and quality. In this study, we conducted QTL mapping on grain size using a recombinant inbred line (RIL) population derived from a cross between japonica variety Beilu130 (BL130) and indica variety Jin23B (J23B). A total of twenty-two QTL related to grain length (GL), grain width (GW), grain length-to-width ratio (LWR), grain thickness (GT), and thousand grain weight (TGW) were detected under two environments, and 14 of them were repeatedly detected. Two minor QTL, qTGW2b and qGL9, were validated and further delimited to regions of 631 kb and 272 kb, respectively. Parental sequence comparison of genes expressed in inflorescence in corresponding candidate regions identified frameshifts in the exons of LOC_Os02g38690 and LOC_Os02g38780, both of which encode protein phosphatase 2C-containing protein, and LOC_Os09g29930, which encodes a BIM2 protein. Scanning electron microscopy (SEM) analysis revealed that the increase of cell size rather than cell number caused the differences in grain size between NILs of qTGW2b and qGL9. Quantitative RT-PCR analysis showed that the expression levels of EXPA4, EXPA5, EXPA6, EXPB3, EXPB4, and EXPB7 were significantly different in both qTGW2b NILs and qGL9 NILs. Our results lay the foundation for the cloning of qTGW2b and qGL9, and provide genetic materials for the improvement of rice yield and quality.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s11032-022-01328-2.
摘要:
水稻籽粒大小是决定籽粒产量和品质的关键因素。在这项研究中,我们使用重组自交系(RIL)种群对籽粒大小进行了QTL定位,该种群来自粳稻品种Beilu130(BL130)和in稻品种Jin23B(J23B)之间的杂交。共有22个QTL与粒长(GL)相关,晶粒宽度(GW),晶粒长宽比(LWR),晶粒厚度(GT),在两种环境下检测到千粒重(TGW),其中14人被反复检测到。两个小QTL,qTGW2b和qGL9进行了验证,并进一步界定为631kb和272kb的区域,分别。在相应候选区域的花序中表达的基因的亲本序列比较确定了LOC_Os02g38690和LOC_Os02g38780外显子中的移码,这两个外显子都编码含蛋白磷酸酶2C的蛋白质,和LOC_Os09g29930,其编码BIM2蛋白。扫描电子显微镜(SEM)分析显示,细胞尺寸而不是细胞数量的增加导致qTGW2b和qGL9的NIL之间的晶粒尺寸差异。定量RT-PCR分析表明,在qTGW2bNIL和qGL9NIL中,EXPA4,EXPA5,EXPA6,EXPB3,EXPB4和EXPB7的表达水平均存在显着差异。我们的研究结果为qTGW2b和qGL9的克隆奠定了基础,为水稻产量和品质的提高提供了遗传材料。
■在线版本包含补充材料,可在10.1007/s11032-022-01328-2获得。