2010 Annual Report 1a.Objectives (from AD-416) Phenotype a soybean mapping population for environmental stress factors. 1b.Approach (from AD-416) Random inbred lines (RILs) are nearing final stages of development and 192 RILs will be selected for marker assisted mapping of resistance genes. The RILs will be assayed for single nucleotide polymorphisms to identify markers for mapping. The RILs will be assessed for response to drought, iron deficiency chlorosis, salt stress, aluminum stress, and ozone stress. Injury scores and DNA marker results will be related through QTL analysis. 3.Progress Report This research relates to inhouse objectives: Quantify the combined effects of elevated carbon dioxide and ozone concentrations on soil carbon dynamics in a soybean-wheat field crop system; quantify the effects of temperature on the physiology, biomass production and seed yield of selected crop plants under conditions of elevated carbon dioxide and ozone; and identify soybean germplasm with enhanced growth and yield potential under elevated levels of carbon dioxide and ozone, and determine the underlying mechanisms and associated genes that control plant responses to these gases. The project was officially started on May 1, 2010. The main accomplishment was the advancement of the soybean breeding population that will be used for application of DNA markers and abiotic stress screening. During the fall of 2009 and winter of 2010 244 individual F5 plants were grown in the in Raleigh greenhouses. F5-derived progeny rows are being grown for maximum seed increase in MN field plots through a specific cooperative agreement with the University of MN. Leaf tissue will be harvested from each progeny row in the vegetative stage for DNA isolation and subsequent SNP marker assay. Harvested seed from this increase will serve as test material for subsequent abiotic stress screening. Other activities included filling a USDA-ARS post-doctoral position to support this project. This person will be located in Raleigh, NC as a member of the Plant Science Research Unit. The project was monitored by email and telephone calls with the cooperating principal investigator.