Increased Female Fertility Associated with the ms1 Locus in Soybeans1

Segregation for male sterility was observed in an F3 line of the soybean, Glycine max (L.) Merr., cross L67‐533 ✕ ‘SRF 300’ and designated as the Urbana Male Sterile (UMS). Segregation in this line and between‐ and within family segregation the following generation indicated UMS was controlled by a single recessive gene pair. Crosses made with the North Carolina Male Sterile (NCMS), ms1ms2, suggested that UMS and NCMS were controlled by the same gene or a different allele at the same locus. Male‐sterile plants of UMS had higher levels of female fertility than did male‐sterile plants of NCMS in various genetic backgrounds and in two diverse environments. The increased female fertility of the UMS male‐sterile plants was expressed as a higher frequency of plants with at least one 3‐seeded pod and a lower frequency of plants with no seed.