Isopropyl-N(3-chlorophenyl) carbamate (CIPC) induced chromosomal loss in soybean: a new tool for plant somatic cell genetics.

The properties and uses of tissue culture partial haploid soybean cell lines are explored. Partial haploid lines were prepared by CIPC treatment of a genetic heterozygote, and compared to this heterozygote and to homozygous cell lines corresponding to the parental genotypes from which the heterozygote was derived. Cell lines which lack chromosomes were characterized physiologically and with respect to a variety of isozyme markers. Often the loss of chromosomes revealed a phenotype corresponding to a recessive parental genotype. In some cases, however, new phenotypes were observed indicating a complex genotype and suggests the interaction of several genes. The implications of this for plant breeding are discussed.CIPC also was used as a tool to dissect a complex phenotype which arose as the result of mutagenesis. A mutant cell line which required asparagine for growth but also had acquired the ability to grow on allantoin as a sole source of nitrogen was treated with CIPC to remove chromosomes. The requirement for asparagine could be separated from the ability to use allantoin, demonstrating that these phenotypes were the result of separate mutations.