Cytogenetic studies in the Andropogon gayanus-Andropogon tectorum Complex in Southwestern Nigeria
DOI:
https://doi.org/10.36253/caryologia-1580Keywords:
Andropogon gayanus, Andropogon tectorum, Apomixis, Kiwani, Meiotic studyAbstract
The studies were carried on accessions of the Andropogon gayanus-Andropogon tectorum complex (Poaceae) in southwestern Nigeria to determine the chromosome numbers and meiotic dynamics in the species. This involves meiotic chromosome and pollen studies using standard procedures. Studies on the morphology and meiotic behaviour of collections of A. gayanus (2n = 40) and A. tectorum (2n = 20, 40) have been made. The cytogenetic studies show that the chromosome configuration of A. gayanus is a tetraploid (2n = 40) on a basic chromosome number of 10. A. tectorum occurs as a regular diploid on a chromosome number of 2n = 20 and it is the only species found in Ekiti State. Accession “Kiwani” was found to be a polyploid. A. tectorum with a chromosome number of 2n = 40. This study has also established the stability of the genome of the Andropogon complex. In spite of the occurrence of univalent and multiple associations, meiosis ensures a high percentage of pollen grains. The pollens of accession “Kiwani” (> 35 µm) were generally larger than those of other accessions while the other accessions of both A. gayanus and A. tectorum have modal pollen sizes less than 35 µm, although the A. tectorum accessions were generally smaller. The study concluded that the occurrence of the tetraploid (2n = 40 in accession AT10, “Kiwani” can be attributed to apomixis occurring in a lonely plant.
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References
Baker, H. G. (1967) Support for Baker’s Law-as a rule. Evolution 21: 853–856.
Bogdan, A. V. (1977) Pasture and Fodder Plants (Grasses and Legumes), Longman Press, New York, U.S.A. page 1– 39, 229 – 231.
Bowden, B. N. (1963) Studies on Andropogon gayanus Kunth. I. The use of Andropogon gayanus in Agriculture. Empire Journal of Experimental Agriculture, 31: 267 - 273.
Chlleda, H. R. and Crowder, L. V. (1982) Tropical Grassland Husbandry, First edition, Longman, London, p. 346 - 367.
Clayton, W. D. (1962) A Key to Nigerian Grasses. Government Printer, Kaduna. Nigeria, pp. 86.
Clayton, W. D. (1969) In Hutchinson, J. and Dalziel, J. M. (Flora of West Tropical Africa, Vol. 111(2), 2nd ed. (Revised by F. N. Hepper). Crown Agents for Overseas Governments and Administration, London.
Faluyi J. O., and Olorode, O. (1987) Aspects of the dynamics of meiosis in nymphal and adult populations of Zonocerus variegatus L. (Orthoptera: Pyrgomorphidae). Ife Journal of Science, 2 (1 and 2): 51 – 61.
Forster, W. H. (1962) Investigations preliminary to the production of cultivars of Andropogon gayanus. Euphytica, 11: 47 – 52.
Hojsgaard, D. (2018) Transient Activation of Apomixis in Sexual Neotriploids may retain genomically altered states and enhance Polyploid Establishment. Frontiers in Plant Science, doi:10.3389/fpls.2018.00230
Hutchinson J, Dalziel J. M. (1972) Floral of West Tropical Africa Vol. III Part 2 –Crown Agents, London,
p. 459 - 461.
Jackson, R. C (1962) Documented chromosome numbers of plants. Madrono 16: 266 – 268.
Laosebikan, B. A. and Olorode O (1972) Morphological variation and cytological aberrations in natural populations of Zonocerus variegatus L. (Orthoptera: Pysrogomorphidal) Bull Entomological Society of Nig, 3:127– 133.
Lowe J. (1989) The Floral of Nigerian Grasses. 2nd ed. Ibadan University Press, p. 214.
Okoli, B. E. (1978) Genetic Studies in the Andropogon gayanus – Andropogon tectorum (Gramineae) Complex in Nigeria. Ph. D Thesis (Unpublished) submitted to the Department of Botany, University of Ife, Osun State, Nigeria.
Okoli, B. E. (1983) Hybridization, Polyploidy and Apomixis in Andropogon tectorum Schum.and Thonn. (Gramineae). New phytologist, 93(4): 591 – 597.
Okoli B. E. and Olorode O (1983) Cytogenetic studies in the Andropogon gayanus- A. tectorum Complex (Gramineae). Botany Journal of Linnean Society, 87: 263 – 271.
Olorode, O. (1972) Cytological studies in some Nigerian Andropogoneae. Nigeria Journal of Science, 6(1):13– 19.
Olorode, O. (1984) Taxonomy of West African Flowering Plants. (Revised ed.) Longman Group Limited Publishers, London, p 123 – 127.
Pagot, J. (1993) Animal Production in the Tropics, 1st edition, Macmillan Press, London, pp. 163 -181, 224 - 225.
Schinkel, C. F., Bernhard K., Agnes S. D., Simone K, Manuela W, Stefan D, Elvira H (2016) Correlations of polyploidy and apomixis with elevation and associated environmental gradients in an alpine plant. Annals of Botany
Singh, D. N. and Godward, M. B. E. (1961) Cytological studies on the Gramineae. Heredity, 15:183 – 197.
Stanfield, D. P. (1970) The Floral of Nigeria Grasses. (1st ed.) University of Ibadan Press, Ibadan, p. 83.
Stebbins, G. L. (1950) Variation and Evolution in Plants, New York, Columbia University Press, 643.
Stebbins, G. L. (1970) Variation and Evolution in Plants: Progress using the Past Twenty Years, Essays in Evolution and Genetics in Honor of Theodosius Dobzhansky 173 – 208.
Swanson, C. P. (1968) Cytology and Cytogenetics, 2nd edn. Prentice-Hall Inc., New Jersey.
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