|Holland, J - IOWA STATE UNIVERSITY|
|Lewers, K - IOWA STATE UNIVERSITY|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 7, 1997
Publication Date: N/A
Interpretive Summary: Chromosomes are the structures that carry genetic information from one generation to another. The soybean plant has the male sex organs and the female sex organs within the same flower. We have identified a soybean plant that is male-sterile, but female fertile. The chromosomes carry many traits or characters called genes. Sometimes these genes are close together on the chromosome and they are said to be linked. Alternatively, the genes may be far apart and they are said to be independent. We have created, through genetic manipulation, a male-sterile female-fertile plant that is linked to flower color. This genetic linkage can be used to produce hybrid soybean seed in large quantities. Plant breeders can use this system, and eventually, improved varieties, with greater yield potential, could be released to the farmer.
Technical Abstract: Recombination values in plants are influenced by genetic factors, environmental conditions, and their interactions. In soybean, Glycine max L. Merr., the cosegregation method to produce hybrid seed depends upon the close linkage of the Ms6 (pollen fertility) locus and the W1 (flower color) locus. Twenty-four near-isogenic lines cosegregating at the Ms6 and W1 loci, (Ms6 ms6 W1 w1), were developed with the ms6-w1 donor cytoplasm and the recurrent parent cytoplasms. The objectives were to determine the recombination values between the Ms6-W1 loci from both testcross and F2- family data. The recombination values between the Ms6-W1 loci from the testcross data in the ms6-w1 donor cytoplasm was 3.14 +/- 0.80 and in the recurrent parent cytoplasms was 3.62 +/- 0.89. From the F2-family data, the recombination value for the Ms6-W1 loci in the ms6-w1 donor cytoplasm was 3.06 +/- 0.35 and in the recurrent parent cytoplasms was 4.90 +/- 0.35. .The recombination values for the F2-family data were statistically significantly different (P=0.05) for the ms6-w1 donor cytoplasm versus the recurrent parent cytoplasms. The recombination values are acceptable, however, to continue to use the cosegregation method to produce hybrid soybean seed. Hybrid seed can be produced in large quantities and used in plant breeding programs to produce populations. Selections from segregating populations can be tested fro agronomic performance and released as germplasm or varieties. The cosegregation method is an efficient way to produce seed.