Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 30, 1999
Publication Date: N/A
Interpretive Summary: This is a Germplasm Release, no Interpretive Summary Required.
Technical Abstract: UMN 3176 is an ineffectively nodulated regenerating alfalfa (Medicago sativa L.) germplasm that was developed to permit introduction of new traits into alfalfa by Agrobacterium-mediated transformation and regeneration of transgenic plants in tissue culture in a genetic background that is incapable of utilizing nitrogen (N) from the atmosphere through symbiotic N2-fixation. Ineffective Agate and Ineffective Saranac plants were crossed onto 68 clones of a regenerating genotype Regen-SY to produce the SYN1. All SYN1 progeny of both crosses were effectively nodulated. Approximately 210 SYN1 plants were randomly intercrossed to produce SYN2 seed. The SYN2 progeny segregated 2970 nodulated to 280 (8.6 %) ineffectively nodulated plants. Approximately 59% (56/95) of the ineffective plants regenerated from leaf tissue. Plants that regenerated and were ineffectively nodulated were intercrossed to produce SYN3 seed (UMN 3176) for distribution. The SYN3 population had 98% ineffectively nodulated and 55% regenerating plants.