Limiting transpiration rate in high evaporative demand conditions to improve Australian wheat productivity

Abstract Limited-transpiration rate at high evaporative demand (‘LTR’ trait) has potential to improve drought adaptation, crop water productivity and food security. The quantification of the implications LTR for consumption, biomass accumulation yield formation requires use dynamic modelling simulate physiological environmental processes interactions in target environments. Here, a new transpiration module was developed Agricultural Production Systems sIMulator (APSIM NextGen) used atmospheric edaphic stress on wheat crops. This parameterized with (i) data from lysimeter experiment assessing genotypic variability trait four genotypes contrasting efficiency, (ii) more pronounced response demand. improving investigated across Australian wheatbelt over 1989–2018. simulated allow an increase national by up 2.6 %, mostly due shift pattern, alleviation deficit during grain filling period higher harvest index. Greatest gains were found north-east (4.9 average) where heavy soils conserved be available later critical stages. effect enhanced under future climate scenario, particularly north-east. Limiting demands appears promising selection breeders, especially drought-prone environments crops heavily rely stored soil moisture.