Submitted to: Maize Genetics Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/1/2002
Publication Date: 3/1/2002
Technical Abstract: Progeny from interspecific and intergeneric cross hybridizations result in novel nuclear-cytoplasmic genetic interactions. In contrast to the usually biparentally inherited nuclear genome, inheritance of mitochondrial and chloroplast genomes will vary depending on the mechanisms regulating transmission to an organism. Only rudimentary knowledge of these phenomena is currently available. Obtaining better information about organellar transmission is necessitated by the substantial impact that nuclear-organelle interactions have on genetic fitness and population dynamics. This basic information will also have applications in both bioengineering based and traditional agriculture. Organelle transgenics is a new avenue to bioengineer cultivars and create value-added crops. The attractiveness of this approach over nuclear transgenics is partly derived from high-level foreign protein expression capabilities and the expectation for transgene containment through strict maternal organelle inheritance. Paternal and bi-parental organelle transmission does occur however, and may be augmented by wide hybridizations. A rapid molecular assay for discerning organelle genomes would be highly useful for deciphering the genetic regulation of their inheritance. This would also provide the means to address organelle transgene containment, and other germplasm issues involving the cytoplasm. This research reports on the identification of cleaved amplified polymorphisms (CAPs) between maize and Tripsacum ssp. organelles. CAPs were detected for four of the five tested chloroplast loci and at least two good candidates for mitochondrial loci. Both chloroplast and mitochondrial markers were used to investigate the organellar origin(s) of the purported natural interspecific Tripsacum-maize hybrid, T. andersonii.