Leaf rolling is an important morphological trait in wheat (Triticum aestivum L.) that is strongly correlated with photosynthesis, transpiration, and respiration, especially in abiotic stress conditions. The identification of quantitative trait loci (QTLs) and genes underlying leaf rolling is essential for wheat breeding. In this study, the ethyl methanesulfonate (EMS) induced mutant Y536 was isolated in a Nongda 3753 background with extreme abaxial leaf rolling. The F₂ and F_2:3 populations derived from a cross between Jing411 and mutant Y536 with contrasting leaf rolling morphologies were developed to map the locus controlling leaf rolling. A public SSR marker was isolated on chromosome 6DL that had a high linkage level with leaf rolling index (LRI). QTL analysis revealed a stable QTL associated with LRI, named QLRI.cau-6D, which explained 7.69 to 10.86% of the total phenotypic variation and had LOD scores ranging from 10.00 to 13.32. TraesCS6D02G237000 (TaHDZIV-D1) was identified as the priority candidate gene according to coding sequence differences between the two parents and gene functional annotations. Consistently, knocking out TaHDZIV-A1/B1/D1 in common wheat line ‘JW1’ significantly increased the LRI compared to the wild type, while overexpression of TaHDZIV-D1 in ‘JW1’ significantly reduced the LRI until the leaves rolled in the opposite direction. Moreover, genetic evidence suggested that TaHDZIV-A1/B1/D1 affects leaf rolling in a dose-dependent manner. Collectively, these findings provide novel insights into the genetic basis of leaf rolling in common wheat.

Heterosis, the phenomenon in which hybrids outperform their parents, has been utilized in maize (Zea mays L.) for over 100 years. To provide a more complete understanding of heterosis, we collected a comprehensive transcriptome and translatome dataset on seedling leaves for B73, Mo17, and their F₁ hybrid, which provided a dynamic landscape of transcriptomic and translatomic variation in maize. Although additivity accounted for a large proportion of variation at two omics-levels, an elevated nonadditive effect was observed in the translatome, especially in the translated subgenome maize1 genes, and the genes that switched from additivity in the transcriptome to nonadditivity in the translatome were significantly enriched in the subgenome maize1. Many genes with allele-specific expression and translation show dramatic regulatory switches between the transcriptome and translatome, and partial genes with allele-specific translation underlying regulatory mechanism also exhibited subgenome bias. Interestingly, we found the translated isoforms show different expression patterns compared with transcriptome and more genes changed their dominant isoforms during the genetic flow from parents to the hybrid at the translatome level. The translated genes with switched dominant isoforms significantly biased to the subgenome maize2 while genes with conserved dominant isoforms significantly enriched in subgenome maize1. Together, the dynamic changed patterns in translatome across hybrid and parental lines show translational fractionation of the maize subgenomes, which may be associated with heterosis in maize and provides a potential theoretical basis for breeding.