Genome engineering barley root system architecture

Our initial aim was to assess the impact on root system architecture from knockout and modifying expression of the barley C-TERMINALLY ENCODED PEPTIDE RECEPTOR (CEPR1) gene. In doing this, we have shown barley cv. Golden Promise possessing a knockout cepr1 allele produces a narrower seedling seminal root angle which translates to mature root system that is steep, compact and dense when grown in a temperature-controlled glasshouse. cepr1 barley plants do however produce significantly less grain compared to WT. Through sequencing the CEPR1 locus in a global barley diversity panel we have found that CEPR1 is highly conserved and is likely critical to the plant’s survival and reproduction. Therefore, we have targeted additional genes for editing which are known to exert control of root system architecture and are differentially expressed between WT and cepr1. We have done this to produce further root system diversity and minimise trade-offs to key agronomic traits including yield. Finally, we aim to assess the performance of cepr1 barley lines under both drought conditions and in the field, where the advantage of steeper roots may be more valuable than the well-watered conditions assessed previously.