A PERENNIAL × ANNUAL MEDICAGO CROSS

We successfully crossed perennial Medicago sativa L. (2n = 4x = 32) and annual M. scutellata (L.) Mill. (2n = 4x = 32). The hybrid was a mixoploid. The primary shoot was hexaploid. Later a tetraploid shoot was identified and another tetraploid shoot had a distinct flower color (dark purple). Somatic chromosome number was unstable, which probably led to chimeral sectoring. Chromatographically the hybrid was documented by species-specific phenolic substances. The hybrid was perennial, but color of the vegetative parts and stem number of the hexaploid sector resembled the annual parent. Flower color of the hexaploid was purple like the perennial; the short peduncle and self-tripping mechanism were like the annual. Leaflet number was unstable, varying from 2 to 6 per leaf. Several characters were intermediate between the parents. Pollen stainability of the hexaploid was low, and no seed was obtained from selfing, backcrossing to either parent, or crossing to Chilean and nondormant M. sativa plants. Other sect...