A DH population was used to map the quantitative trait locus (QTL) contributing to HMF. Three traits including anther emergence rate (AER), anther emergence score (AES) and pollen production score (PPS) of the haploid population were evaluated at two locations. We also applied genomic selection to HMF traits, and found satisfied results which might be usefull for breeding.
Three new haploid inducers were developed for screening immature haploid embryos during in vivo haploid induction. MAS of both qhir1 and qhir8 was used for inducers breeding, the efficiency improve greatly.
Here, we present the discovery that mutation of a non-Stock6-originating gene in qhir8, namely, ZmDMP, enhances and triggers haploid induction. ZmDMP was identified by map-based cloning and further verified by CRISPR–Cas9-mediated knockout experiments.
Twin embryo seeds was found during in vivo haploid induction, an enhanced HI ability can increase twin-embryo kernel frequency, and the observed high frequency of both haploid twin-embryo kernels and aneuploidy provides new evidence for chromosome elimination during HI in vivo. The results also provide new ideas for studying the effect of phytohormone with twin-embryo kernel.
The success of modern maize breeding has been demonstrated by remarkable increases in productivity over the last four decades. However, the underlying genetic changes correlated with these gains remain largely unknown.