2018 West Lafayette Simulation of 18 Sorghum Hybrids

<p>The second stage of analysis involves model calibration where the "SorghumXMLOutput" file from the first stage is adjusted by comparing the APSIM simulated results and measured phenotypes. The APSIM files used in the calibration procedure are reported in "2018 West Lafayette Simulation of 18 Sorghum Hybrids". The calibration steps produce the adjusted physiology parameters for each of the 18 sorghum hybrids and are reported in the “SorghumXMLOutputUQ” file.</p>

<p>In the following simulations, APSIM (version 7.9, built number is r4044) software is required. <a href="https://www.apsim.info/download-apsim/">https://www.apsim.info/download-apsim/</a></p>

<p>The APSIM files from West Lafayette 2018 (WL18) were used in model calibration.  The files to run the simulation are documented in “2018 West Lafayette Simulation of 18 Sorghum Hybrids” but the output files are not included. The simulated text files for the 18 hybrids can be generated by running the simulations in APSIM.  For this simulation, the APSIM file (WL18.apsim) was used to run the simulation with weather data (WL18.met) and parameter file (SorghumXMLOutput).</p>

<p>Based on the comparison of simulated and the observed results from these trials, some adjustments to the SorghumXMLOutput file were made by adding parameters tt_endjuv_to_init, tt_flag_to_flower, and partition_rate_leaf to all hybrids based on the leaf appearance rate and observed flowering time as described by Hammer et al. (2010).  Trudan Headless and Sordan Headless hybrids are photoperiod sensitive so the parameter photoperiod_slope was added to these genotypes to reflect the late flowering time for these varieties. Average leaf appearance rate 1 was used for all 18 hybrids and APSIM default values were used for leaf appearance rate 2. These adjustments were included in the "SorghumXMLOutputUQ" file. </p>