Judge the Weak to Assess the Strong: Identifying Determinants of Wheat Standability

Plant standability is an important trait for maximizing yield potential and is always assessed in breeding programs. If a plant lodges and the shoot becomes permanently displaced from an upright position this negatively impacts photosynthetic capacity, grain harvest, and seed quality. Furthermore, standability must be taken within its context – it is complex with contributing traits also impacting biomass partitioning and grain productivity. With the ultimate goal of improving cultivar development, we have built a collaboration that is (a) focusing on defining and understanding the physiological components contributing to standability to (b) provide a basis for us to identify preferred alleles and markers in Canadian germplasm. To date, we have developed capacity within our collaboration to assess stem biomechanics, structural carbohydrate deposition, and soluble carbohydrate mobilization. We have assessed the aforementioned traits in field grown material from select Canadian cultivars and two bi-parental wheat populations and have discovered significant associations between select traits. Further, to discover underlying genetic components involved in standability-associated traits we have performed linkage mapping and accomplished a preliminary RNA-sequencing experiment for gene expression associated with increased stem strength.