Recently, researchers from Biotechnology Research Institute (BRI) of Chinese Academy of Agricultural Sciences (CAAS), in collaboration with South China Agricultural University etc. reported their research results in a paper entitled “De novo genome assembly and analyses of12 founder inbred lines provide insights intomaize heterosis” published in the internationally reputed journal “Nature Genetics”.
Hybrid maize displays superior heterosis and contributes over 30% oftotal worldwide cereal production. However, the molecular mechanismsof heterosis remain obscure. Here researchers show that structural variants (SVs)between the parental lines have a predominant role underpinning maizeheterosis. De novo assembly and analyses of 12 maize founder inbred lines(FILs) reveal abundant genetic variations among these FILs and, throughexpression quantitative trait loci and association analyses, they identifyseveral SVs contributing to genomic and phenotypic differentiationsof various heterotic groups. Using a set of 91 diallel-cross F1 hybrids, they found strong positive correlations between better-parent heterosis of theF1 hybrids and the numbers of SVs between the parental lines, providingconcrete genomic support for a prevalent role of geneticcomplementationunderlying heterosis. Further, they document evidence that SVs in both ZAR1and ZmACO2 contribute to yield heterosis in an overdominance fashion. These results should promote genomics-based breeding of hybrid maize.
Dr. Baobao Wang, doctoral student Mei Hou from the BRI, Dr. Junpeng Shi from China Agricultural University, Dr. Lixia Ku from Henan Agricultural University, Dr. Wei Song from Beijing Academy of Agriculture & Forestry Sciences, and Dr. Chunhui Li from Institute of Crop Sciences (CAAS) are the co-first authors of this research. Professor Haiyang Wang (South China Agricultural University), Jingsheng Lai (China Agricultural University), Jiuran Zhao (Beijing Academy of Agriculture & Forestry Sciences)and Yanhui Chen (Henan Agricultural University) are the corresponding authors. This work is funded by National Key R&D Program of China (2021YFF1000301), National Natural ScienceFoundation of China (32022065, 32130077,31871639), the Major Program of Guangdong Basic and AppliedResearch (2019B030302006), the Beijing ScholarsProgram (BSP041) and the Agricultural Science and TechnologyInnovation Program of CAAS.
More information can be found through the link:https://www.nature.com/articles/s41588-022-01283-w |