The Decision Support System for Agrotechnology Transfer (DSSAT) Version 4.6.

The Decision Support System for Agrotechnology Transfer (DSSAT) is one of the most widely used cropping system models across the globe. It has been used in many applications, including precision agriculture, plant breeding, crop management, climate change and climate variability, water use and irrigation management, yield forecasting, and many others. Since the release of DSSAT Version 4.5 in 2011, it has been downloaded by over 4,800 users. DSSAT includes utilities to prepare the input files for soil, weather and crop management and observed data files for comparison with simulated data. DSSAT also now includes two programs to help with the estimation of the genetic coefficients, including GLUE and GenCalc. There are several applications for analysis of the simulated outcomes including two graphics programs and the seasonal and sequence or crop rotation programs. In 2014 we released DSSAT Version 4.6 that includes minor coding updates to most of the modeling components, as well as models for new crops, including canola and pigeon pea. The ORYZA2000 model was added as a second option for the simulation of rice growth, development and yield and a separate cassava module was created. DSSAT Version 4.6 also includes a new sensitivity analysis program for evaluation of a range of inputs related to genetics, crop management and weather. The source code of the Cropping System Model (CSM) of DSSAT will be distributed via the GitHub web site to facilitate the participation by a larger group of users for code development. We will present some of the new advancements and developments of the updated DSSAT compared to previous versions.