BREEDING PERSPECTIVES AND PROGRAMS AT EAST LANSING J. Mitchell McGrath 1 *, Linda Hanson 1 and Rachel Naegele 2 1 USDA-ARS, Sugarbeet and Bean Research Unit, and 2 Plant Breeding and Genetics Program; Department of Crop and Soil Sciences, 494 Plant and Soil Sciences Building, Michigan State University, East Lansing, MI 48824-1325 Abstract: USDA-ARS sugar beet breeding activities for both Aphanomyces resistance and CMS / O-type conversion at East Lansing reach back to the 1940’s, with variety testing activities at Michigan State University reaching back to circa 1911. Many of those contributions are well known in the sugar beet breeding community, and this contribution serves to update this community on the current breeding activities at East Lansing. The overall goal is to produce germplasm enhanced in one or more traits for release to the seed industry for ultimate incorporation into modern hybrids. Along this trajectory, germplasm is being developed for genetic analyses of traits important to the Great Lakes and Eastern U.S. growing regions. Two broad breeding methods are being deployed, each with multiple components. Open pollinated methods are being used to recombine existing germplasm releases to effect genetic progress through selection in the Eastern agro-environment. Selfing is being employed to create inbreds for genetic analyses. Both approaches result in populations that form one of the three essential legs of modern sugar beet breeding. The other two legs, phenotyping and markers, are also being developed. The relative efforts applied to these three legs needs to be balanced against available resources. Introduction: Recent germplasm releases at East Lansing have focused on developing and improving sucrose content in a shallow root-groove character that sheds soil harvested with the beets and thus minimizes the spread of disease from improperly disposed tare dirt (e.g. SR96 & SR97; McGrath 2003). Disposal of tare dirt is costly. This ‘smooth-root’ trait reduces adhered soil on beets by ca. 50%, promising a savings of $2 million to Michigan factories alone. Changing the root architecture was initiated in the 1940’s, however agronomic and disease resistance limitations delayed its adoption. Currently, this germplasm is reasonably well adapted to the Eastern U.S. and is currently being deployed by industry. Its remaining limitation is low tolerance to damping-off and crown and root rot caused by Rhizoctonia solani AG2-2. The rhizomania resistance gene Rz1 has been incorporated into this background (e.g. EL0204; McGrath & Lewellen 2004). The smooth-root germplasm stream is serving, and will continue to serve, as our recurrent parent for introgression of new characters, such as sugarbeet cyst nematode resistance and salt-tolerant germination, as well as introgressing Rhizoctonia resistance from existing improved germplasm (see below). These populations are derived from traditional open-pollinated methods of sugar beet selection, including mother root selection in disease and agronomic nurseries, seed production in the winter greenhouses, and progeny testing in both the lab and the field. The inability to sufficiently discriminate between phenotypic variance due to genotype or environment in open-pollinated populations of sugar beet is well known, and numerous methods have been suggested to alleviate this concern, including doubled haploids and clonal propagation, however little substantial progress has been made in separating these variance