Stable transformation of alfalfa (Medicago sativa L.) was obtained by
particle bombardment of calli (derived from petiole and stem sections
cultured for three weeks on SH medium), followed by delayed selection
with 50 mg/l kanamycin on BOi2Y medium. Selection at a lower level of
kanamycin (25 mg/l) in late stages of culture resulted only in escapes
. Analysis of seven transgenic plants revealed that all were derived f
rom one transformation event. Segregation of the neomycin phosphotrans
ferase gene in test cross progeny followed a 1:1 Mendelian ratio for a
single locus insertion in a heterozygous state.