The inbred line Ky27--white endosperm and purple plumule--was selected for inclusion in a survey for genetic variation among the polypeptides of the chloroplast thylakoid membrane. Analysis was conducted using a modified Laemmli SDS gradient-density PAGE system. A certain wild type protein band migrating faster than the Bio-Rad 14.4 Kd marker was absent from Ky27.
The source of first seed was from Marcus Zuber (USDA/University of Missouri), who recalls that it was in the breeders' seed collection here when he arrived in the late forties.
A second accession was obtained from E. H. Coe, who obtained it from J. B. Beckett (both USDA/University of Missouri). Beckett pedigrees this line back to 1955 when he obtained it from R. W. Jugenheimer, while at the University of Illinois. It also has white endosperm, purple plumule, and absence of the protein band.
P. L. Pfahler of the University of Florida/Gainesville contributed original seed from the University of Kentucky, marked "Lot 1959-3." The three phenotypic markers are as above.
C. G. Poneleit of the University of Kentucky supplied several lines originally derived from the land variety "Boone County White": Ky21, Ky27, Ky30A, Ky39, Ky56, and Ky122. A few other lines have been lost. Pfahler supplied two lots of Ky49. All lines mentioned in this listing are white endosperm and none, including the Ky27, has purple plumule. The Ky27 (lot 75/2050-54) is not missing a protein band, but Ky122 (lot 72/1016-20) does have that phenotype.
I conclude that the strain Ky27 currently supplied by the University of Kentucky differs from earlier releases, and that the genetic variation affecting expression of a chloroplast membrane protein was probably in the original Boone Co. White population. Though one might most trust seed supplied by the original breeding station, genetic shifts can and do occur!
Stephen A. Modena
Return to the MNL 58 On-Line Index
Return to the Maize Newsletter Index
Return to the Maize Genome Database Page