Maize is an important oil seed crop and a major food crop in different parts of the world. Since maize has relatively lower seed oil content as compared to other oil crops, efforts are continuing to improve its oil content percentage. In this study, we analyzed two contrasting maize genotypes with differential oil accumulation percentages. High oil-content (HOC) maize had 11% oil content while low oil-content (LOC) maize had significantly lower oil content (5.4%). Transmission electron microscopy revealed a higher accumulation of oil bodies in the HOC maize embryo as compared to LOC maize. Comparative RNA-sequencing analysis at different developmental stages of the seed embryos identified 739 genes that are constantly differentially expressed (DEGs) at all the six developmental stages from 15 days after pollination (DAP) to 40 DAP. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified fatty acid metabolism and fatty acid biosynthesis as the most enriched biological pathways contributed by these DEGs. Notably, transcriptional changes are more intense at the early stages of embryo development as compared to later stages. In addition, pathways related to oil biosynthesis and their corresponding genes were more enriched at 30 DAP, which seems to be the key stage for oil accumulation. The study also identified 33 key DEGs involved in fatty acid and triacylglycerols biosynthesis, most of which were up-regulated in HOC, that may shape the differential oil contents in the two contrasting maize. Notably, we discovered that both acyl-CoA-dependent and acyl-CoA-independent processes are essential for the high oil accumulation in maize embryo.

The 8029AB line is a dominant genic male sterility (DGMS) two-type line in Brassica napus L., which can be used in a three-line approach for the seed production of rapeseed hybrids. Genetic analyses have demonstrated that the sterility of 8029A is controlled by a single dominant nuclear gene (BnMS5^e) interacting with one recessive gene (BnMS5^c). Six pairs of penta-primer amplification refractory mutation system (PARMS) markers were designed according to the sequence of BnMS5^a, BnMS5^c and BnMS5^e. Two pairs of these PARMS markers were successfully identified and validated. The PARMS markers MS5-1Fc/MS5-1Ft/MS5-1R12 could distinguish BnMS5^c from BnMS5^a/BnMS5^e, and the PARMS markers MS5-2Ft/MS5-2Fa/MS5-1R12 could genotype BnMS5^a and BnMS5^c/BnMS5^e. The combination of these two pairs of PARMS markers could be used to identify the presence or absence of BnMS5^a/BnMS5^c/BnMS5^e effectively. Consequently, marker-assisted selection can be carried out in the early generation to shorten the breeding period and improve the breeding efficiency.