The autopolyploid nature and severe segregation of hybrid progenies of many crop plants, such as sweet potato, hinder genetic studies and molecular breeding. Novel technology tools are required to combat such challenges. On January 8, 2021, Molecular Plant published an article, entitled "Genome-wide identification of agronomically important genes in outcrossing crops using OutcrossSeq", by scientists from the CAS Center for Excellence in Molecular Plant Science in cooperation with Shanghai normal University, Chinese Academy of Forestry Sciences, and other institutions.

Using three types of tested populations of outcrossing plants, the scientists developed OutcrossSeq, a new method for the construction of high-density genotypic maps. Compared to the existing methods, OutcrossSeq improves the efficiency of genotyping, mapping, genetic characterization, and breeding of outcrossing plants. The high-quality genotypic map generated by OutcrossSeq, combined with phenotypic investigation of the experimental populations, can be directly used for high-precision genetic mapping. Taking the hexaploid sweet potato as an example, the researchers applied OutcrossSeq to analyze the data of various agronomic characters (leaf shape, leaf color, tuber number, root skin color, etc.) and gene expression of hybrid populations，and identified the genetic loci and candidate genes controlling these traits. This method sufficiently solves the problem of genetic mapping of outcrossing polyploid species. It is also suitable for functional gene mapping of other outcrossing species, thus providing a set of efficient and accurate solutions for genetic analysis, molecular breeding, and genomic selection of complex traits in many outcrossing crops.

The study has been funded by the National key Research and Development Program, the Chenshan Botanical Garden Basic Project Program, and the Chinese Academy of Sciences.

Contact:
Dr. Peng Zhang, Professor
National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences (CEMPS), Chinese Academic of Sciences
Tel: 86-21-54924096
Email: zhangpeng@cemps.ac.cn
Article link：https://www.cell.com/molecular-plant/fulltext/S1674-2052(21)00003-4
Tool link：http://www.xhhuanglab.cn/tool/OutcrossSeq.html