Use of Simulation Models for Evaluating High Input Production Practices in Corn in Georgia.

Corn yield can be affected by numerous factors and because every field is different, increasing corn yield across all environments is not easy. It is crucial to implement a proper soil fertility program that will be the foundation for achieving high yields. Nitrogen (N), phosphorous (P), potassium (K), and micronutrients should be applied at the right time and right amounts to ensure no in-season deficiencies arise. Moreover, tillage method, planting date, population, and proper rotation are factors that can keep yields consistently high. There are studies that have aimed to increase corn yield around the world by considering these variables. Moshia et al. (2008) tried to assess the influence of variable rate manure applications on grain yield by using three different management zones in northeastern Colorado. Another study showed that optimized irrigation can have positive results in increasing corn yield (Li & Sun, 2016). In this three-year study the objectives were to measure the agronomic response of corn to high yield management practices and use crop simulation models to evaluate additional management scenarios. The main goal of this study was to determine the effect of high fertility management strategies on corn in Georgia. Two treatments regarding high fertilization rates were tested in a 1.78 ha field, located in Tifton, GA. Conventional management practices were implemented during the first year of the project while intensive ones were implemented the following two years. Soil samples were collected before and after each growing season, while tissue samples were collected during multiple growing stages from V3 to R4. The field data are being used for calibrating and evaluating the DSSAT CERES Maize model. The model is being used to conduct sensitivity analyses to identify the limiting factors in corn production and inform Georgia growers on how to sustainably intensify corn production.