Identification of the genes conferring resistance to European corn borer (ECB) [Ostrinia nubilalis (Hübner)] is an important step in understanding how resistance is expressed and whether different sources of maize (Zea mays L.) germplasm can be combined to enhance protection. The locations of genes for resistance to ECB tunneling have been reported but are inconsistent across studies. The objectives of this study were to map and characterize quantitative trait loci (QTL) for resistance to tunneling in De811 and compare these with related studies and with QTL for anthesis and ear height. Inbred De811 (resistant) was crossed to susceptible inbred B73 to produce a population of 147 F3 lines. The population was artificially infested and evaluated in three environments. The F3 lines were genotyped at 88 restriction fragment length polymorphism (RFLP) loci to facilitate QTL mapping with composite interval mapping (CIM). Seven QTL for ECB tunneling were detected on chromosomes 1, 3, 4, 5, and 8, associated with 42% of the phenotypic variation. The F1 exhibits partial dominance for resistance but only one QTL with dominant gene action was observed. An F3 population of B73 × B52 that was evaluated in the same environments facilitated comparisons of genetic heterogeneity between inbreds De811 and B52. Only one QTL for tunneling was common between the populations, indicating that the two inbreds may contribute different genes for resistance in crosses with B73. This information could be useful for combining the favorable alleles of De811 and B52.

Modern plant breeding has progressed by incorporating knowledge from many disciplines. It has become clear that developments in plant biotechnology have potentially significant application to plant breeding, but it has been and shall remain a challenge to determine how to best integrate advances in this field into graduate curricula. To gain a broader perspective on this topic, we surveyed public and private sector plant breeders and research administrators regarding their graduate and professional training experience and opinions on the utility of plant biotechnology in plant breeding programs. We report and discuss survey results and identify possible avenues for integrating plant biotechnology into graduate plant breeding training programs. The 508 responses were equally divided among the private and public sectors. Plant breeders were optimistic about the potential importance of their knowledge of plant biotechnology. Examination of course programs suggest plant breeders feel well prepared for their profession; however, there seems to be some need to increase exposure to plant pathology, molecular genetics, molecular biology, and cell biology. More recent graduates have incorporated some of these areas through graduate research activities. Opportunities for integration were apparent through seminar topic selection, modest course addition, and postgraduate training programs for graduate students and faculty. The goal of graduate plant breeding programs should remain constant: educating scientists, producing materials, and identifying knowledge leading to production of plant germplasm having the desired characteristics. This goal will be achieved by scientists trained to critically assess developments in plant biology and integrate them into plant breeding research programs.

Jon Tollefson. Thank you also to Dr. Richard Wilson for standing in for my dissertation defense. I am truly grateful to Wendy Woodman whose laboratory expertise and cooperation was imperative in making these studies possible. A special thank you to fellow graduate students Lance Veldboom, Peter Freymark, Sue Jarboe, and David Austin. Thanks for the help, the friendship, and the encouragement. We've been through much together, and I'll never forget the many good times we had. To my wife Luann, who shared with me the triumphs and pains during these years as a graduate student. I could always count on your steadfast love and support. To our daughters, Leah and Mary, who have come to us during the course of my student career. God has truly blessed us with the love and joy that you have provided. And finally, I would like to thank ray parents, Theresa and Jerome Brinkman, the two people who inspired within me a love for farming and a foundation in the practice of agriculture. 1 GENERAL INTRODUCTION Dissertation Organization This dissertation was written in the form of two manuscripts. The first manuscript reports the results of restriction fragment length polymorphism (RFLP) analysis performed to estimate the genetic location and effects of quantitative trait loci (QTL) affecting resistance to secondgeneration European corn borer. The second manuscript reports the results of RFLP mapping of QTL affecting five morphological traits including plant and ear heights, growingdegree-days to 50% pollen-shed and 50% silk emergence, and silk-delay. The manuscripts are preceded by a General 16 I. GENETIC LOCATION AND CHARACTERIZATION OF CHROMOSOMAL REGIONS AFFECTING SECOND-GENERATION EUROPEAN CORN BORER RESISTANCE IN A MAIZE POPULATION Written for submission to the journal Crop Science