2005 Annual Report 4d.Progress report. This report serves to document research conducted under a Specific Cooperative Agreement between ARS and The Ohio State University. Additional details of this research project can be found in the report for the parent CRIS 3607-21000-008-00D Develop New or Improved Methods of Hydroponic and Greenhouse Production and Pest Protection. This SCA officially began April, 2005. Petunia was selected for study because it is one of the top selling bedding plants nationwide, much is known about petunia from a molecular standpoint, and petunia is commonly produced with high rates of fertilizer. An initial study began in June, 2005 in a unique 12-chamber controlled environment system in Wooster, OH, wherein 2 levels of fertility (100 and 400 ppm N) are being used to produce petunia plants in 3 light levels (100, 300, and 500 µmol m-2 s-1, 16-h day). Petunia growth suffers in the high fertility treatment, especially in low-light environments. The 12-chamber system enables us to investigate many interactions between environment and fertility in a single study.