Polycross‐Progeny Testing of Red Clover (trifolium pratense L. 1

Investigations were conducted into the feasibility of breeding red clover ( Trifolium pratense L.) for persistence utilizing polycross‐progeny testing. Approximately 1,500 clones of red clover were vegetatively increased and selected for virus tolerance in nurseries. Ultimately, 20 clones were selected for polycross progeny testing. Seed produced on the 20 clones under conditions of random pollination were sown at two locations. Persistence of clones was correlated with persistence of progenies, but the value of progeny testing was indicated because only a portion of the variability in persistence could be recognized by clonal evaluation alone. Yields of progenies were greatly different only in the 3rd year at which time persistence was expressed. Earliness of bloom of the first growth was implicated in previous and in the present research as being associated with lack of persistence. No correlation existed between earliness of the first crop with that of the second crop. Earliness of the first growth was transmitted to progenies but because of the practice of harvesting seed from the second‐crop growth, selection for earlinesss was eliminated in these genetic materials. Use of the polycross test in the breeding of red clover for persistence appears to have been effective in view of the genetic gain made in the selected materials. Further gains should be possible when the most persistent of the 20 clones are combined into a synthetic variety.