2003 Annual Report 4.What were the most significant accomplishments this past year? D. Progress Report: This report serves to document research conducted under a specific cooperative agreement between ARS and the University of Illinois. Additional details of research can be found in the report for the parent project, 3625-21000-036-00D, Enhancing Agronomic and Value-Added Traits of Corn Germplasm. This is a new project begun in the 2003 nursery and field experiments. The general objective of this project is the development of maize varieties with host plant resistance (HPR) against the European corn borer (ECB) and the Western corn rootworm (WCR) as well as an improved resistance against Fusarium as major components of an integrated pest management system. The specific objectives are to (1) evaluate Germplasm Enhancement of Maize (GEM) lines for their resistance against WCR as well as first and second generation ECB, (2) evaluate GEM lines for their resistance against Fusarium species, (3) determine the association between insect resistance and fumonisin concentration in GEM germplasm, study the genetic basis of insect resistance in maize against both insect species by diallel crosses and testcrosses. (5) Initiate a recurrent selection program aimed to develop new maize lines with improved multiple insect resistant (MIR). The main approach of this project is to initially screen advanced GEM material for ECB, WCR, and Fusarium resistance. This germplasm comprises populations containing 25% exotic germplasm and inbred lines that were derived from these. Choice of germplasm for this study was obtained from reviewing data from previous GEM Public Cooperator Reports, and discussions with the GEM Coordinator. As a contingency plan populations with 50% exotic germplasm and other exotic source populations (100% exotic germplasm) will be evaluated for resistance if the advanced germplasm does not show promising levels of resistance. Fifteen populations containing 25% percent exotic germplasm were selected, which combined resistance against WCR and ECB with acceptable agronomic performance (see Table. 1)by screening available GEM data sets. In addition, ten lines derived form the non-Stiff Stalk population AR17056:N2025 and five from the Stiff Stalk population CUBA117:S1520 S5 lines were selected. Separate field trials were conducted to determine ECB and WCR resistance for populations and lines. Both experiments were conducted in adjacent fields at Urbana, Illinois. The experimental design was a generalized lattice design with four replications and two-row plots for the line experiment and four-row plots for the population experiment. Rows were 0.75m apart and 1.5m long. Ten to 12 plants were hand planted per row. All experiments were planted May 13, 2003. Plants were manually infested with ECB larvae to ensure an even infestation level for the entries. The artificial infestation with first generation larvae (1ECB) was performed June 26 and 27, 2003. The artificial infestation with second generation larvae (2ECB) was performed July 24 and 25, 2003. The manual infestation was synchronized with the natural appearance of 1ECB and 2ECB moths to simulate natural infestation. Egg masses for manual infestation with ECB larvae were purchased from the Mass Rearing Laboratories, Inc., Madrid, Iowa. For manual infestation, egg masses were applied directly into the plant whorl (1ECB) and into the axils of the first leaf above and below the ear (2ECB). About four egg masses per plant were applied two times at daily intervals, accounting for about 180 larvae per plant and generation. In the line experiment all plants within the first row of a plot were artificially infested with 1ECB egg masses, whereas the second row was infested with 2ECB larvae. In the population experiment 1ECB egg masses were applied to all plants in the first row and 2ECB egg masses to all plants in the third row. Leaf feeding damage was rated on a 1 to 9 scale July 16, 2003. The WCR treatment was planted in a WCR trap crop area to ensure a high level of infestation. Damage to WCR larval root feeding was measured on five random plants per plot in the line experiment and on ten plants per plot in the population experiment. Root injury was assessed using the Iowa State 0-3 damage rating scale August 4, 2003. In addition to the evaluation experiments, all evaluated populations were increased in the Urbana maize summer nursery. Per population, 12 individual plants were selfed to initiate the development of new inbred lines.