Submitted to: Genetic Resources and Crop Evolution
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/26/1998
Publication Date: N/A
Citation: Interpretive Summary: There are a number of different clover species that have been observed in the past in nature, but no seed was available for research use in the U.S. seed collection. A wide variety of these clovers have been observed in Bulgaria. Collecting trips were made to Bulgaria in 1990 and 1993 to collect seed of some of these clovers. A total of 246 seed collections of 50 different clovers from the southern half of Bulgaria were made during these trips. Seed was collected from four clovers not in the U.S. collection. Also, additional collections were made of many different clovers that previously only had a few populations in the U.S. collection. These trips increased the genetic diversity of the U.S. clover collection. In the future, researchers may find valuable traits or transfer useful genes from clovers obtained in these trips that will benefit U.S. and world agriculture.
Technical Abstract: Joint collecting expeditions to improve the genetic diversity of Trifolium species in the U.S. National Plant Germplasm System (NPGS) were carried out in Bulgaria by scientists of the USDA-ARS, University of Florida, Texas A&M University, and Institute of Introduction and Plant Genetic Resou (IIPGR), Bulgaria, on 14-27 July 1990 and 30 July to 13 August 1993. The objectives were to collect seed of T. vesiculosum Savi and other annual clovers in southeastern Bulgaria in 1990 and seed of perennial Trifolium species in southwestern Bulgaria in 1993. A total of 246 collections were made of 50 Trifolium species (38 annual and 12 perennial) and 25 collections of 17 other forage legumes. Collections were made at 90 sites in 13 of the 20 floristic regions in Bulgaria. The genetic diversity of T. vesiculosum in the NPGS was increased by the addition of 16 accessions. Four Trifolium sp. were added to the NPGS. Land utilization for intensive grazing near villages and small plot farming in river valleys greatly increased between 1990 and 1993. Genetic erosion of the extensive Trifolium resources within Bulgaria may occur as these practices increase.