An entry consisting mostly of plants having little to no seed set was found amidst the breeding material of Dr. Walter R. Fehr (Iowa State University) in 1975. The entry was descendent from germplasm population AP6(Sl)Cl, which was described by Fehr and Ortiz (1975). Investigations have revealed that partial male sterility was the primary cause leading to reduced seed set (Stelly, 1979).
Stelly, David M. and Palmer, Reid G.
"Research notes: A partially male-sterile mutant in soybeans,"
Soybean Genetics Newsletter: Vol. 6
, Article 23.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol6/iss1/23