Male sterility gene ms 1 from North Carolina was transferred to maturity groups I, II, and III over the last few years to facilitate the use in Wisconsin of the twinning and haploidy phenomena associated with ms1ms1 plants. In 1975 we had an extended fall growing season and seed was obtained from several hundred male sterile ms 1ms1 plants, representing maturity groups I, II, III, IV, and V. Honey bees were used as pollinators.
Bingham, E. T.; Beversdorf, W. D.; and Cutter, G. L.
"Research Notes: Progress in Obtaining Soybean Haploids 2n=20,"
Soybean Genetics Newsletter: Vol. 3
, Article 29.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol3/iss1/29