Vegetative and Reproductive Characteristics of Trifolium rubens.
Bradley C. Venuto, USDA-ARS Grazinglands Research Lab, 7207 W Cheyenne Street, El Reno, OK 73036
Identification of introduced or native legumes with forage, biomass or nitrogen producing potential continues to be a priority need. Trifolium rubens (L.) is a perennial legume with an origin and distribution of Eurasia, southern Europe from Poland to Albania and Italy, southern Russia, and Turkey. The research objective was to evaluate all available T. rubens accessions for morphological and reproductive traits including seed production. Seed of 10 accessions was provided by the U.S. National Plant Germplasm System, Regional Plant Introduction Station, Pullman, Washington. The quantity of seed ranged from 30 to 100 seed per accession. Two replications of 10 spaced plants were established for each entry on 5 May 2004. At the end of the establishment year, plant survival was not different among accessions and ranged from 85 to 100%. Survival ratings taken on 5 April 2006 also were not different with a mean of 83.5% and a range of 70 to 93% (accessions 542923 and 31559, respectively). Establishment year survival and second year survival were correlated (R = 0.57; P < 0.0001). Differences were observed among accessions for all vegetative characters evaluated including height, vigor, growth habit and leaf characteristics. Date of flowering and seed production varied among accessions. Seed per plant ranged from 0 to 0.6g per plant in the establishment year (accessions 255396 and 314123 respectively) and from 0 to 27.5 seed per flower in 2005 (accessions 255396 and 314123, respectively). Results from evaluation of this limited number of plants revealed significant useful variation existed among accessions of this species. Further work in progeny evaluation and selection of T. rubens is warranted.