Investigating gas-exchange performance between wheat landraces and commercial varieties

Improvement of photosynthetic traits in crops to increase yield potential and crop resilience has recently become a major breeding target. Synthetic biology and genetic technologies offer unparalleled opportunities to create new genetics for photosynthetic traits driven by existing fundamental knowledge. However, large “gene bank” collections of germplasm comprising of historical collections of crop species and their relatives offer a wealth of opportunities to find novel allelic variation in the key steps of photosynthesis, to identify new mechanisms and to accelerate genetic progress in crop breeding programs. Here we explore the available genetic resources in food and fibre crops, strategies to selectively target allelic variation in genes underpinning key photosynthetic processes and deployment of this variation via gene editing in modern elite material.
Gas-exchange data presented:
A subset of Vavilov wheat landraces from a single seed descent and four commercial checks (Mace, Baxter, Banks and Pastor) were grown in 2 x 3m plots in the field (Yanco, NSW - 2018). Commercial checks represent current elite and older released commercial varieties. A-Ci curves were measured on the youngest fully expanded leaf for n=2-3 plants between 10 - 4pm at an irradiance of 1500 PAR.
Analysis of data to determine Vcmax and J:
Using PlantEcoWrap (Stinziano et al., 2020) and the wheat kinetic parameters determined by Kane et al. (1994) and Prins et al. (2016) with the wheat gmes and gamma star from Silva-Perez et al. (2017). The data was normalised to 25oC using the Ea for Kcair and gmes from tobacco (Bernacchi et al., 2002).