Mapping QTLs for Fertility Restoration of Different Cytoplasmic Male Sterility Types in Rice Using Two Oryza sativa ×O. rufipogon Backcross Inbred Line Populations

Abstract

Hybrid rice breeding using cytoplasmic male sterility/fertility restoration (CMS/Rf) systems plays an important role in ensuring global food security. Two backcross inbred line (BIL) populations derived from either Xieqingzao B (XB)//XB/Dongxiang wild rice (DWR) (XXD) or XB//DWR/XB (XDX) were used to detect quantitative trait loci (QTLs) for fertility restoration of Dwarf wild abortive- (DA-), Indonesia Paddy- (ID-), and DWR-type CMS in rice. Lines with ID- and DA-type CMS were testcrossed with both the XXD- and XDX-BILs, while the line with DWR-type CMS was testcrossed with the XDX-BILs only. A total of 16 QTLs for fertility restoration of CMS systems were identified, including three for DWR-type CMS, six for DA-type CMS, and seven for ID-type CMS. All of the additive alleles in the QTLs were derived from Oryza rufipogon. Eleven QTLs were clustered in five chromosomal regions, indicating that common Rf loci restored different CMS systems, and the favorable O. rufipogon alleles could be used to develop restorer lines for various CMS types by marker-assisted selection.

Genetic Analysis of Novel Fertility Restoration Genes (qRf3 and qRf6) in Dongxiang Wild Rice Using GradedPool-Seq Mapping and QTL-Seq Correlation Analysis

“…qRf1 partially coincides with a fertility restoration QTL reported by Li et al [42], encompassing the Rf3 position of CMS-WA-type [16,24]. qRf10.1 was reported by Li and Hu [32,45], and it aligns with the CMS-WA-type Rf3 documented by Yao et al [46]. qRf10.2 concurs with the fertility QTL intervals from Li et al [42] and Hu et al [32], as well as with the qRf10 interval of the CMS-DA type identified by Xie et al [33], which is also involved in the recovery of the CMS-WA type of fertility [22,28,47].…”

“…The effects were cumulative and influenced by minor genes. Eight QTLs for restoring fertility in CMS-DA-type cytoplasmic sterility have been located on chromosomes 1, 5, 9, and 10 [32][33][34]. These QTLs were mainly on chromosomes 1 and 10, contributing between 2.9% and 43.2%.…”

Molecular tagging of Rf genes for the fertility restoration of WA-CMS system by bulk segregant analysis in rice

“…Molecular mapping of the Rf genes provides a powerful tool to develop restorer lines avoiding extensive test crossing with CMS lines (Hu et al 2016). Molecular tagging of the fertility restorer gene will help in its transfer to other desirable agronomic background without involving a sterile cytoplasm or extensive test crossing with CMS lines.…”

Deployment of wild relatives for genetic improvement in rice (Oryza sativa)

“…Among the cultivated species, high yielding O. sativa grew widely across the globe and low yielding African Rice O. glaberrima is endemic to West Africa. Despite their inferior plant type, seed shattering, poor yield and grain parameters, wild species are rich reservoirs of a novel genes/QTLs for traits like resistance to various biotic stresses (Bhasin et al., 2012; Dong et al., 2020; Ikeda et al., 1990; Khush et al., 1990; Zhang et al., 2000; Sarao et al., 2016; Yang et al., 2020), tolerance to abiotic stresses (Brar & Khush, 2006; Cao et al., 2020; Lei et al., 2013; Luo et al., 2016; Zhang et al., 2017), economically important traits like grain yield (Balakrishnan et al., 2020; Gaikwad et al., 2014; Luo et al., 2011; Xiao et al., 1996), grain quality (Gaikwad et al., 2018; He et al., 2017; Qi et al., 2018), cytoplasmic male sterility (Hu et al., 2016; Zebing & Yingguo, 1988), fertility restoration (Gaikwad et al., 2014) and heterosis for yield contributing traits (Xiao et al, 1998…”

“…Elite parental lines can be improved for yield using favourable genes from wild/related species. This species has contributed fertility restorer genes for various CMS systems in cultivated rice (Hu et al., 2016). The identification of yield‐enhancing genes/QTLs from wild rice and introducing them into parents of hybrid rice would dramatically enhance heterosis in rice hybrids (Wu, 2009; Xiao et al., 1996).…”