Antonio is Professor Emeritus (retired) and was Professor of Agronomy, Nutrient Management Research and Extension Specialist, until December 31, 2023, at Iowa State University (ISU). He continues activities, however, by finishing research reports and articles, helping finish his graduate students, and contributing to ISU Extension for areas within his expertise. He has focused on phosphorus, potassium, lime, micronutrients, manure nutrients management, soil testing and plant analysis, use of precision agriculture technologies, and management impacts on phosphorus loss from fields. He has been co-responsible for ISU Extension nutrient management guidelines, contributed to the development of the Iowa Phosphorus Index and the Iowa Nutrient Reduction Strategy. He has represented ISU at the USDA/NIFA North Central Region Committee for Soil Testing and Plant Analysis and the committee Minimizing P Losses from Agriculture. He served at the North American Proficiency Testing Program oversight committee and served 6 years as Associate Editor of both Agronomy Journal and Soil Science Society of America Journal. He co-developed the ISU Extension Soil Fertility website and continues helping maintain it.