HETEROGENEITY OF MAIZE CYTOPLASMIC GENOMES AMONG MALE-STERILE CYTOPLASMS

1 United States Department of Agriculture, Agricultural Research Service, Florida-Antilles area, and Department of Plant Pathology, University of Florida, Gainesville, Florida 32611
2 Department of Genetics, North Carolina State University, Raleigh, North Carolina 27606

Maize mitochondrial and chloroplast DNA's were prepared from normal (fertile) lines or single crosses and from members of the T, C, and S groups of male-sterile cytoplasms. Restriction endonucleases HindIII, BamI, EcoRI, and SalI were used to restrict the DNA, and the resultant fragments were electrophoresed in agarose gels. The results show that the N (fertile), T, C, and S cytoplasms each contained distinct mitochondrial DNA (mtDNA). These distinctive patterns were unaffected by nuclear genotype. No evidence of paternal inheritance of mtDNA was observed. Chloroplast DNA (ctDNA) from the N, C, and T cytoplasms was indistinguishable by HindIII, SalI, or EcoRI endonuclease digestion. The S cytoplasm ctDNA, however, was slightly different from that of other cytoplasms, as indicated by a slight displacement of one band in HindIII digests. The molecular weight of maize ctDNA was estimated to be as high as 88 x 106. Estimates of the minimum molecular weight of maize mtDNA ranged from 116–131 x 106, but the patterns were to complex for an unambiguous determination. Based on HindIII data, a comparison of the molecular weight of mtDNA bands common to the N, T. C, and S cytoplasms suggests that C cytoplasm most closely resembles N cytoplasm. The T and S sources are more divergent from the C and N cytoplasms. These results indicate a possible gradation of relatedness among male-sterile cytoplasms. The marked variation in mtDNA, with apparently less variation in ctDNA, represents circumstantial, but compelling, evidence that mtDNA may be involved in the male sterility and disease susceptibility traits in maize.

Submitted on July 28, 1977
Revised on January 10, 1978




This article has been cited by other articles:


Home page
GeneticsHome page
J. O. Allen, C. M. Fauron, P. Minx, L. Roark, S. Oddiraju, G. N. Lin, L. Meyer, H. Sun, K. Kim, C. Wang, et al.
Comparisons Among Two Fertile and Three Male-Sterile Mitochondrial Genomes of Maize
Genetics, October 1, 2007; 177(2): 1173 - 1192.
[Abstract] [Full Text] [PDF]


Home page
ScienceHome page
C. S. LEVINGS III, B. D. KIM, D. R. PRING, M. F. CONDE, R. J. MANS, J. R. LAUGHNAN, and S. J. GABAY-LAUGHNAN
Cytoplasmic Reversion of cms-S in Maize: Association with a Transpositional Event
Science, August 29, 1980; 209(4460): 1021 - 1023.
[Abstract] [PDF]