Optimizing triticale sowing densities across the Mediterranean Basin

Triticale and wheat are similar crops, but triticale represents a valuable alternative to wheat due to its greater biomass production and grain yield in Mediterranean-type growing conditions. However, despite the higher yield potential and increasing importance of this crop, there are no dynamic crop models available to assist triticale adaptation via simulation experiments. In a previous study, the APSIM-Nwheat model was parameterized for triticale resulting in a new APSIM-Triticale model but the new model was never compared with detailed experimental triticale data in a one-to-one comparison. Here, the new model was tested with detailed field experimental observations. APSIM-Triticale was able to reproduce phenology, biomass, grain yields and soil water dynamics. The model performed well over several years and management options that included different sowing densities, sowing dates and a short and tall cultivar. The tested model was then used to explore management options to maximize triticale yield across the Mediterranean Basin. The response to sowing density was cultivar and rainfall-environment dependent. The simulation analysis indicated that there was no yield advantage with higher sowing densities with a tall cultivar type in high yielding environments, despite its higher biomass growth rates. The highest yields were achieved at the early sowing date at the sowing densities between 100 and 300plants/m² in the high rainfall regions for both short and the tall cultivars. The simulation study suggests that sowing a short cultivar with a reduced radiation use efficiency but early vigour growth could increase current yields across different regions, seasons and management options in the Mediterranean climate.