Summary
Important morphological features such as plant height, leaf size and number of leaves, shape of the panicle and sessile spikelets, staminate condition of the pedicellate florets, nature of lemma, colour of the stigmatic surface and seeds etc., were studied in 8 Sorghum species and 10 F1 hybrids between them. Based on the data, interrelationship amongst the species are discussed.
Pachytene pairing was complete and apparently normal, followed by regular meiosis at later stages resulting in high pollen stainability and good seed setting in all the parental species except the male sterile “Kafir”. Studies on the pairing properties of the differentially stained regions showed that synapsis starts from the proximal to the distal end and separation of the split chromosomes starts from the distal to the proximal.
The interspecific hybrids studied are classified into four types based on pachytene pairing and pollen sterility. 1. normal pairing accompanied by high pollen fertility, 2. normal pairing accompanied by partial pollen sterility. 3. irregularities in the pachytene pairing followed by partial pollen sterility and 4. irregularities in the pachytene pairing accompanied by normal pollen fertility. Suitable explanations are advanced to explain the meiotic aberrations noted in some of the hybrids under study.
Cytogenetical mechanisms underlying species differentiation in the Eu-Sorghum species are discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Garber, E. D., and J. Gorsic: The genus Collinsia II. Interspecific hybrids involving C. heterophylla, C. concolor and C. sparsiflora. Bot. Gaz. 118, 73–77 (1956).
Goldschmidt, R. B.: Theoretical genetics. Univ. California Press 1958.
Magoon, M. L.: Genetical and cytological studies in the genus Sorghum. Proc. 2nd. All. Ind. Millet. Conf. Kanpur 1961.
—, D. C. Cooper and R. W. Hougas: Cytogenetic studies of some diploid Solanums, section Tuberarium. Amer. J. Bot. 45, 207–221 (1958).
—, and K. R. Khanna: Haploids. Caryologia (Firenze) 16, 191–235 (1963).
- P. L. Manchanda and M. S. Ramanna: Cytological and morphological studies in the genus Sorghum. Cytologia (Tokyo) (in press) (1963).
—, and M. S. Ramanna: Comparative karyomorphology of Eu-Sorghums. Caryologia (Firenze) 14 (3), 391–407 (1961a); - Cytology of some „Eu-Sorghums.“ Genet. iber. 13, 129–144 (1961b).
— and K. G. Shambulingappa: Desynapsis and spontaneous chromosome breakage in Sorghum purpureo-sericeum. Indian J. Genet. 21, 87–98 (1961).
—, S. Ramanujam and D. C. Cooper: Cytogenetical studies in relation to the origin and differentiation of species in the genus Solanum L. Caryologia (Firenze) 15, 151–252 (1962).
—, and K. G. Shambulingappa: Karyomorphological studies in Sorghum ankolib Var. annalib red-A Eu-Sorghum. Indian J. Genet. 20, 166–177 (1960); - Karyomorphology of Sorghum propinquum and its bearing on the origin of 40-chromosome Sorghums. Chromosoma (Berl.) 12, 460–465 (1961); - Cytological and morphological studies of some interspecific hybrids in Eu-Sorghums. Z. Vererb.-Lehre 93, 14–24 (1962a); - Cyto-morphological studies on some species and species hybrids in the genus Sorghum. Züchter; 32, 317–324 1962b); - A polyhaploid plant in Sorghum almum. Genet. polo. 3, 301–306 (1962c); Studies on polyploids in the genus Sorghum. Genet. iber. (in press) (1963).
Magoon, M. L., K. G. Shambulingappa and M. S. Ramanna: Chromosome morphology and meiosis in some Eu-Sorghums. Cytologia (Tokyo) 26, 236–252 (1961b); - A polyhaploid plant in Sorghum halepense Pers. Curr. Sci. 30, 347–348 (1961c).
Müntzing, A.: Sterility and chromosome pairing in intra-specific Galeopsis hybrids. Hereditas (Lund) 24, 117–188 (1938).
Shambulingappa, K. G., and M. L. Magoon: Cyto-morphological studies in the genus Sorghum. Indian J. Genet. 23 (in press) (1963).
Sharma, A. K., and D. Bhattacharjee: Chromosome studies in Sorghum I. Cytologia (Tokyo) 22, 287–311 (1957).
Stebbins, G. L.: Cytogenetic studies in Paeonia II. The cytology of the diploid species and hybrids. Genetics 23, 83–110 (1938).
Stephens, S. G.: The internal mechanism of speciation in Gossypium. Bot. Rev. 16, 115–149 (1950); Species differentiation in relation to crop improvement. Crop. Sci. 1, 1–5 (1961).
Swaminathan, M. S., and M. L. Magoon: Origin and cytogenetics of the commercial potato. Advan. Genet. 10, 217–256 (1961).
— and K. L. Mehra: A simple propionocarmine PMC Smear method for plants with small chromosomes. Indian J. Genet. 14, 87–88 (1954).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Magoon, M.L., Shambulingappa, K.G. Cyto-morphological studies op some species and hybrids in the Eu-Sorghums. Chromosoma 14, 572–588 (1963). https://doi.org/10.1007/BF00326512
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00326512