Crop Science Journal of Natural Resources and Life Sciences Education
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


Published in Crop Sci 16:63-66 (1976)
© 1976 Crop Science Society of America
677 S. Segoe Rd., Madison, WI 53711 USA
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Levings, C. S.
Right arrow Articles by Hu, W. W. L.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Levings, C. S., III
Right arrow Articles by Hu, W. W. L.
Agricola
Right arrow Articles by Levings, C. S.
Right arrow Articles by Hu, W. W. L.

Cytological Characteristics and Nuclear DNA Bouyant Densities of Corn, Teosinte, Tripsacum, and Corn-tripsacum Hybrids1

C. S. Levings, III, D. H. Timothy and W. W. L. Hu2

This study assesses the variability in buoyant density of nuclear DNA (nDNA) of corn and its relatives and the effect of several cytological phenomena on the demity of nDNA. The nDNAs of four Tripsacum L. spp., corn (Zea mays L.), annual teosinte (Z. mexieana [Schrad.] Kuntze), perennial teosinte (Z. perennis [Hitchc.] Reeves and Manglesdorf), and corn-tripsacum hybrids were characterized for buoyant densities. Corn and perennial teosinte nDNA densities were similar but were significantly greater than those of tripsacum and annual teosinte. The latter two did not differ in densities. The corntripsacum hybrid densities resembled those of the higher parent. However small significant differences in parental base composition did not preclude hybridization. In all cases, and typical of grasses, nDNAs were resolved as single bands without satellites and with relatively high guanine and cytosine contents.

Chromosome numbers of T. andersonii Gray, in ed., Guatemala grass, are reported for the first time (2n = 64). Chromosomal knob numbers of 12 Tripsocum accessions ranged from 0 to 40. One Tripsacum accession had 3 to 4 B chromosomes. The presence of chromosomal knobs and B chromosomes in tripsacums had no effect on the banding pattern and buoyant density of the nDNAs as determined by neutral CsCI analytical eentrifugatinn.

Although similarities and significant differences in buoyant densities of nDNA were found among corn and its relatives, the value of these results for establishing genetic relationships is not clear.

Key Words: Zea spp. • Tripsacum spp. • Chromosome number • Chromosomal knobs • Guanine-cytosine ratios • Maize


1 Paper number 4699 of the Journal Series of the North Carolina Agric. Exp. Stn., Raleigh, NC 27607. Research supported in part by Rockefeller Foundation Grants 6803 and 6905, and NSF Grant GB 4133 for collecting and cytological studiesd.

2 Professors, Deps of Genetics and Crop Science, and research assistant, Dep. of Crop Science, North Carolina State Univ.

Received for publication May 27, 1975.





HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
The SCI Journals Agronomy Journal Vadose Zone Journal
Journal of Natural Resources
and Life Sciences Education
Soil Science Society of America Journal
Journal of Plant Registrations Journal of
Environmental Quality
The Plant Genome
Copyright © 1976 by the Crop Science Society of America.