Genetic studies of a male-sterile, female-fertile soybean mutant
Adilson Luiz Seifert; Leones Alves de Almeida and Romeu Afonso de Souza Kiihl
Studies on a new spontaneous male-sterile / female-fertile soybean mutant identified by the Embrapa Soybean breeding program were carried out in Londrina, PR. The mutant showing segregation for male-sterility (BR93-12879) was selected within F4 progeny lines derived from the IAS-5 (3) X OCEPAR 9-SS1 cross performed in 1993. The F1, F2 and F3 generations of cross among heterozygous plants of the BR93-12879 line and recessive homozygous plants (male-sterile) of the T 266H (ms1ms1), T 259H (ms2ms2), T 273H (ms3ms3), T 274H (ms4ms4), T 277H (ms5ms5) and T 295H (ms6ms6) lines were studied to identify whether the new mutation is conditioned by a new allele or by a mutation in one of the six loci already described in the literature. The F1, F2 and F3 plants from the crosses were visually classified as male-sterile or male-fertile. Results from the allele test and inheritance study among the mutant genotype and the recessive homozygous male-sterile lines (ms1, ms2, ms3, ms4, ms5 and ms6) showed that a single recessive gene controls the male-sterile trait of BR93-12879. This gene is allele to the already described ms1-gene and resulted from a genetic mutation in the ms-loci.