2006 Annual Report 4d.Progress report. This report serves to document research conducted under a Specific Cooperative Agreement between ARS and The University of Toledo. Additional details of research can be found in the report for the parent CRIS 3607-21000-011-00D Develop Improved Technologies for Soilless Greenhouse Plant Production to Minimize Water, Labor, Agrochemical Inputs and Environmental Impacts. The goal of this SCA is to identify the protein and genetic changes during early nutrient deficiency or toxicity stress, a period also known as hidden hunger. Since last year, we have identified 15 boron-stress-induced proteins, identified B-specific genes in the model system Arabidopsis and used that system to identify analogous genes in the floriculture genus Pelargonium that will be useful in developing a test kit for floriculture crops. We have also surveyed over 100 Pelargonium cultivars and 50 Pelargonium species for boron accumulation and non-accumulation, evaluated nutrient uptake and partitioning in diploid and tetraploid Pelargonium, and begun to test the expression of some of those 15 proteins during boron deficiency in Pelargonium in different light environments and determine their impact on gas exchange properties on the whole-leaf level. These studies have resulted in a graduate student completing her Master of Science program in the Earth, Ecological, and Environmental Science Department, a manuscript in preparation, and two oral presentations at regional plant science meetings.