Submitted to: Genome Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/1996
Publication Date: N/A
Citation: N/A Interpretive Summary: Soybean plants for commercial production are male fertile and female fertile and produce many seed per plant. Changes in the reproductive biology of the plant can produce complete sterility or partial sterility. Plants that are genetically male sterile but completely female fertile have been used in plant breeding to produce F1 hybrid seed. Partial male-sterile plants are not of use commercially. Few female (complete or partial-sterile) plants have been described, which most likely reflects the technical complexity of identifying and characterizing the abnormalities. In a previous paper, we described the use of laser microscopy to optical section female tissue in soybean. In this report, we describe genetically and microscopically three separately derived partial-female sterile plants. The male functions normally but on the female all the sex cells carrying the abnormality die so no completely female-sterile plants are produced. The partial-sterile trait can only be carried in the sex cells transmitted by the male. Thus we have plants that are partial female sterile. These plants are useful to study (compare) normal female development with abnormal female development in soybean. The results will be most useful to those studying soybean genetics and plant breeders.
Technical Abstract: Soybean female partial-sterile mutants 2, 3, and 4 (PS-2, PS-3, and PS-4) were recovered from a gene-tagging study. Our objectives were to study 1) inheritance, 2) linkage, 3) allelism, and 4) reproductive biology. For inheritance and linkage tests all three PS mutants were crossed to flower color mutant Harasoy-w4 and to chlorophyll-deficient mutants CD-1 and CD-5. For allelism tests, reciprocal crosses were made among the three partial-sterile mutants. The inheritance studies showed that the three PS mutants must be maintained as heterozygotes because upon self-pollination the heterozygotes segregate 1 fertile:1 partial-sterile plant. Linkage results indicated no linkage between the partial-sterile locus and the CD-1 and the CD-5 loci. The genetic tests confirmed that the gene for partial-female sterility was not transmitted via the female gamete. Therefore to transmit the trait plants must be used as male parent. No differences were observed between normal and partial-sterile genotypes in pollen development, pollen viability, and pollen tube germination. A study of megagametogenesis indicated that the ovules from partial-sterile plants had normal embryo sac development. Ovule abortion was due to failure of fertilization.