Factors Involved in Seed Production of Red Clover Clones and Their Polycross Progenies at Two Diverse Locations 1

To assess the role of differential seed‐producing capacity as a factor in genetic shifts during seed multiplication, we examined seed production of red clover ( Trifolium pratense L.) clones and their progenies at Lexington, Ky., and at Prosser, Wash. Number of heads was the primary factor in governing seed yields per clonal plant. Number of seeds per head and seed weight were of less importance within each of the locations. Clonal and progeny seed yields within and between locations were not correlated. Significant correlations indicated that, at Prosser, early clones produced the most heads and the highest seed yields. Progenies of these clones also produced the highest seed yields. Some evidence suggested that the high yielding progenies were also earlier than average to flower. Although this earliest to flower‐high seed yield relationship was not significant at Lexington, we inferred that it might have been present if seed had been harvested throughout the season rather than from only the regrowth following the harvest of the first crop as hay. This work suggests that the higher seed production by early clones could account for some of the shifts found when red clover seed is multiplied. This indicated the need for further investigation of this possible relationship and the effect of different management practices on natural selection for undesirable forage characteristics.