Persistent Link:
http://hdl.handle.net/10150/281922
Title:
CHROMOSOME MORPHOLOGY IN CYNODON DACTYLON (L.) PERS.
Author:
Brilman, Leah Ann Moore
Issue Date:
1981
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The pachytene bivalents of the tetraploid Cynodon dactylon var. dactylon could all be identified on the basis of characteristic morphological features including knobs, prominent chromomeres, chromosome length, long arm length, short arm length, arm ratio and relative length. The bivalents could be separated into two sets of chromosomes, D and D', with the D genome being homologous to that found in the diploids, C. dactylon vars. aridus and afghanicus. The two sets are homoeologous as shown by the occasional formation of quadrivalents and the closeness of chromosome measurements, although chromomere patterns and knobs differed. C. dactylon var. dactylon therefore appears to be a segmental allotetraploid. In prophase somatic spreads of var. dactylon two sets of chromosomes could also be separated by heterochromatic patterns. In both the diploids, vars. aridus and afghanicus, and the tetraploid the somatic chromosomes could be homologised with their corresponding pachytene bivalents. The chromosomes were of different relative lengths during the two phases. A polyhaploid obtained from a twin seedling of C. dactylon var. dactylon showed both univalents and bivalents in a diplotene spread, supporting a segmental allopolyploid origin of var. dactylon. This plant reverted back to a tetraploid state before further studies could be made. Giemsa C-banding, using barium hydroxide at room temperature for 50 minutes and 2xSSC at 60°C for 30 minutes to pretreat the slides before staining, produced telomeric bands in the position of the knobs seen in standard acetocarmine squash.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Bermuda grass -- Genetics.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Plant Sciences
Degree Grantor:
University of Arizona
Advisor:
Kneebone, William R.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleCHROMOSOME MORPHOLOGY IN CYNODON DACTYLON (L.) PERS.en_US
dc.creatorBrilman, Leah Ann Mooreen_US
dc.contributor.authorBrilman, Leah Ann Mooreen_US
dc.date.issued1981en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe pachytene bivalents of the tetraploid Cynodon dactylon var. dactylon could all be identified on the basis of characteristic morphological features including knobs, prominent chromomeres, chromosome length, long arm length, short arm length, arm ratio and relative length. The bivalents could be separated into two sets of chromosomes, D and D', with the D genome being homologous to that found in the diploids, C. dactylon vars. aridus and afghanicus. The two sets are homoeologous as shown by the occasional formation of quadrivalents and the closeness of chromosome measurements, although chromomere patterns and knobs differed. C. dactylon var. dactylon therefore appears to be a segmental allotetraploid. In prophase somatic spreads of var. dactylon two sets of chromosomes could also be separated by heterochromatic patterns. In both the diploids, vars. aridus and afghanicus, and the tetraploid the somatic chromosomes could be homologised with their corresponding pachytene bivalents. The chromosomes were of different relative lengths during the two phases. A polyhaploid obtained from a twin seedling of C. dactylon var. dactylon showed both univalents and bivalents in a diplotene spread, supporting a segmental allopolyploid origin of var. dactylon. This plant reverted back to a tetraploid state before further studies could be made. Giemsa C-banding, using barium hydroxide at room temperature for 50 minutes and 2xSSC at 60°C for 30 minutes to pretreat the slides before staining, produced telomeric bands in the position of the knobs seen in standard acetocarmine squash.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBermuda grass -- Genetics.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplinePlant Sciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorKneebone, William R.en_US
dc.identifier.proquest8109045en_US
dc.identifier.oclc8673272en_US
dc.identifier.bibrecord.b13900304en_US
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