The power of selection: Dissecting phenotypic plasticity and linkage drag underlying yield traits of rice (Oryza sativa) using selective introgression

Abstract

The power of selection and phenotypic plasticity of seven rice grain yield (GY) traits was dissected using DNA markers and 226 Minghui86 introgression lines (ILs) phenotyped across four contrast environments of long‐day versus short‐day and drought versus irrigated conditions. Linkage mapping identified 77 main‐effect quantitative trait loci (QTLs) plus 15 groups of epistatic QTLs affecting the GY traits. By characterizing genomic introgression patterns of the donor alleles in ILs selected for high‐ and low‐trait values based on replicated progeny testing across each of the four environments and for high‐ and low‐GY across nine different environmental scenarios, 246 QTLs affecting the seven yield traits were identified. Genetic drag from tight repulsive linkage of genes with opposite effects on the same traits was detected in 45 cases involving 90 (35.8%) QTLs, indicating its wide presence in superior Chinese hybrid parents. The demonstrated selective introgression strategy, including the developed ILs plus the genetic information on the associations of introgressed donor alleles with the yield traits in the ILs would provide a useful platform for future breeding by design.

The COG1-OsSERL2 complex senses cold to trigger signaling network for chilling tolerance in japonica rice

“…It is extensive application potential in rice breeding that the epistasis traits of QTL genes depend on the various genetic background 38 – 40 , 51 , such as COG1 . The opposite phenotype of COG1 transgenic rice in japonica and indica background may be explained with a model of genetic incompatibilities: invasion of COG1 disturbs endogenous OsSERL2 indica function, causing MAPK cascade down-regulation in indica background (Fig.…”

“…The identified negative effects can be improved with new technology, such as the gene-editing, to break the linkage drag in molecular breeding. This would promote maintenance of cold-tolerance or other key traits in breeding populations when introgression genes between japonica and indica varieties are used in rice production 51 , 56 .…”

A SLAF-based high-density genetic map construction and genetic architecture of thermotolerant traits in maize (Zea mays L.)

“…Compared with the previous genetic map constructed using SSR molecular markers ( Mei et al., 2006 ; Shi et al., 2022 ), the high-density genetic map constructed by SLAF sequencing technology in this study have the following characteristics: 1, it belongs to the third generation of molecular markers, which is the most abundant molecular marker at the current level; 2. The distribution of molecular markers on each linkage group is more uniform and denser than SSR; 3.…”