In 1975 we reported the ratio of normal pollen grains to coenocytic pollen grains per anther locule of greenhouse grown plants from the original North Carolina line of the ms1 mutant. The observed ratio was 2:1 rather than the expected 4:1 (Palmer and Albertsen, 1975). Cooper and Boerma (1975), working with the Urbana male sterile, and Palmer and Winger (1975), working with Ames, Harosoy, and Urbana male steriles, proposed that the gene(s) conditioning male sterility are located at the same locus as the ms1 gene.
Albertsen, Marc C. and Palmer, Reid G.
"Research Notes: Environmental Influence on Total Pollen Grains per Flower
from Normal and Sterile Plants of the Urbana Male Sterile.,"
Soybean Genetics Newsletter: Vol. 3
, Article 21.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol3/iss1/21