Eliminating Duplicates in Germplasm Collections: A White Clover Example

One area that is often given low priority in the management of many germplasm collections is the elimination of duplicate and genetically redundant accessions. The purpose of this communication is to (i) describe a simple and effective procedure used in the National Plant Germplasm System white clover ( Trifolium repens L.) collection for identifying and eliminating duplicate cultivar accessions, and (ii) discuss the potential gain in management efficiency that results from eliminating duplicates. The Germplasm Resources Information Network and plant inventory books were reviewed to ensure accessions were properly identified and to detect suspected duplicates. Additional historical documentation (plant introduction station card catalogs, acquisition logs, correspondence, and reports) were reviewed to characterize suspect duplicate accessions. Morphological data was obtained to supplement historical information. The white clover collection had 42 cultivars that occurred more than once in the collection, involving 133 of 626 accessions. Based on our review, 35 accessions were retained with no change, 39 accessions were bulked into 16 new accessions, and 59 accessions were designated as inactive, resulting in a net reduction of 82 accessions (13% of total collection). This results in savings of $41 000 ($500 cage −1 ) in regeneration costs alone. Eliminating duplicates is an effective method of reducing germplasm maintenance costs without losing valuable genetic resources.