Research and studies showed newly assembled genomes of 26 different genetic lines of corn, showing the crop’s rich genetic diversity. Detailed in an article published in the journal Science, first author of the study and an associate professor of ecology, evolution and organismal biology at Iowa State University, Matthew Hufford, says that these genomes as references can better help plant scientists select genes that lead to better crop yields or stress tolerance. The first corn genome, mapped in 2009 at Iowa State by Patrick Schnable and Doreen Ware and team, was the genetic line known as B73. Since then, B73 has served as the primary reference genome for corn, and scientists have a limited understanding of genetic sequences in corn genomes that are not in B73. The 26 genomes mapped in the new study, however, encompass a wide range of genetic diversity, including popcorn to sweetcorn to field corn from different geographical and environmental conditions. This genome mapping provides more reference data in order for scientists to combine maize genetics for targets that could lead to better crop performance. The large genetic diversity present in corn, however, creates major hurdles for the creation of new genomes, since 85% of the corn genome is composed of transposable elements. Hufford, comparing these elements to a jigsaw puzzle because the majority of pieces are one color. This repetition makes it harder to determine how the parts fit together. Technological advancements allow tools for researchers to overcome these hurdles, and allows for longer sequence reads, which make the pieces of the puzzle larger and more likely to be arranged properly by scientists.
Link to Article: https://phys.org/news/2021-08-corn-genetic-diversity-genome.html