Submitted to: International Turfgrass Science Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 1, 1997
Publication Date: N/A
Interpretive Summary: Kentucky bluegrass (Poa pratensis L.) is the dominant, or component, turf grass species in 40 million lawns in the U.S. and Canada. Over 75% of all Kentucky bluegrass seed in the U.S. is produced in the Tri-State region of Washington, Idaho, and Oregon. Traditionally, seed production management practices have included open-field burning after harvest to remove residue and stimulate seed production the following year. Field burning, however, produces smoke and particulate pollution of increasing public concern. The USDA-ARS Western Regional Plant Introduction Station, Pullman, WA, currently maintains a collection of diverse Kentucky bluegrass germplasm accessions from 27 countries. Two-hundred twenty-eight accessions and 17 commercial cultivars were evaluated for turfgrass, forage, and seed production factors in field studi studies. Accessions with potentially high seed yield and turf quality were identified and are now being studied in residue management studies to identify genotypes with improved productivity in no-burn management systems.
Technical Abstract: To estimate diversity within the USDA/ARS plant introduction collection of Kentucky bluegrass (Poa pratensis L.), 228 accessions and 17 commercial cultivars were evaluated for turfgrass, forage, and seed production parameters in field studies from 1994 to 1996 at Pullman, WA. Experimental units consisted of 1.0 m strips with 0.31 m spacing between units in randomized complete-blocks with three replications. Significant variability was observed for all phenotypic and agronomic traits. The collection has been characterized by a representative core subset (one random accession chosen from each of 22 clusters) utilizing cluster analysis (Ward method). The core represents approximately 10% of the accessions studied. Clusters were identified that exhibited high seed yield and good turfgrass and forage characteristics. Utilization of this core collection will facilitate genetic resource management, the identification genotypes for turfgrass breeding and other agronomic uses, and the identification of geographic regions offering promise for future germplasm collection. The core subset will allow a wide range of variability in the USDA/ARS Poa pratensis germplasm collection to be evaluated for many traits an in many environments. All data will be available on the Germplasm Resources Information Network (GRIN) database.