Theoretical and Applied Genetics

, Volume 85, Issue 6–7, pp 873–881 | Cite as

Abnormal macrosporogenesis in five alfalfa (Medicago sativa) mutants producing 4n pollen

  • A. Mariani
  • S. Tavoletti
  • F. Veronesi


An analysis of micro- and macrosporogenesis in five diploid alfalfa mutants was carried out using a stain-clearing technique. All plants produced tetranucleated microspores and jumbo pollen due to the complete failure of the postmeiotic cytokinesis as well as bi- and trinucleated macrospores. The latter was due to the absence of cytokinesis after the first and second meiotic division of macrosporogenesis. Only one out of the five clones analyzed formed tetranucleated macrospores as a consequence of the total lack of cytokinesis after both meiotic divisions. The fusion of nuclei within binucleated macrospores resulted in 2n macrospores of the SDR type, recognizable on the basis of nucleolus dimension, confirming the ability of jumbo pollen (jp) mutants to produce 2n eggs at a high frequency. Nuclear fusion was also observed within tri- and tetranucleated macrospores. Although having the same genetic background, the five clones showed significant variability in the expression of abnormal cytokinesis during macrosporogenesis.

Key words

Reproductive mutants Jumbo pollen Alfalfa Cytogenetics Sexual polyploidization 


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  1. Albertsen MD, Palmer RG (1979) A comparative light and electron microscopic study of microsporogenesis in male-sterile (ms 1) and male-fertile soybean (Glycine max (L.) Merr.). Am J Bot 66:253–265Google Scholar
  2. Beadle GW (1931) A gene in Zea mays for failure of cytokinesis during meiosis. Cytologia 3:142–155Google Scholar
  3. Beversdorf WD, Bingham ET (1977) Male-sterility as a source of haploids and polyploids of Glycine max. Can J Genet Cytol 19:283–287Google Scholar
  4. Castetter EF (1925) Studies on the comparative cytology of the annual and biennial varieties of Melilotus alba. Am J Bot 12:270–286Google Scholar
  5. Cutter GL, Bingham ET (1977) Effect of soybean male-sterile gene ms 1 on the organization and function of the female gametophyte. Crop Sci 17:760–764Google Scholar
  6. Gottschalk W, Kaul MLH (1974) The genetic control of microsporogenesis in higher plants. Nucleus 17:133–166Google Scholar
  7. Heyn FW (1977) Analysis of unreduced gametes in the Brassiceae by crosses between species and ploidy levels. Z Pflanzenzuecht 78:13–30Google Scholar
  8. Kennel JC, Horner HT (1985) Influence of the soybean male-sterile (ms 1) on the development of the female gametophyte. Can J Genet Cytol 27:200–209Google Scholar
  9. Mashkina OS (1979) Unreduced microspore formation in sweet cherry. Tsitol Genet 13:343–346Google Scholar
  10. McCoy TJ, Smith LY (1983) Genetics, cytology and crossing behaviour of an alfalfa (Medicago sativa) mutant resulting in failure of the postmeiotic cytokinesis. Can J Genet Cytol 25:390–397Google Scholar
  11. McCoy TJ, Smith LY (1984) Uneven ploidy levels and a reproductive mutant required for interspecific hybridization of Medicago sativa L. x Medicago dzhawakhetica Bordz. Can J Genet Cytol 26:511–518Google Scholar
  12. Peloquin SJ (1983) Genetic engineering with meiotic mutants. In: Mulchay DL, Ottaviano E (eds) Pollen biology and implications in plant breeding. Elsevier Scientific Publ, New York, pp 311–316Google Scholar
  13. Pfeiffer TW, Bingham ET (1983) Abnormal meiosis in alfalfa, Medicago sativa: cytology of 2n egg and 4n pollen formation. Can J Genet Cytol 25:107–112Google Scholar
  14. Steel RGD, Torrie JH (1980) Principles and procedures of statistics: a biometrical approach, 2nd edn. McGraw-Hill, New York, pp 495–520Google Scholar
  15. Stelly DM, Peloquin SJ, Palmer RG, Crane CF (1984) Mayer's hemalum-methyl salicylate: a stain-clearing technique for observations within whole ovules. Stain Technol 59:155–161Google Scholar
  16. Tavoletti S, Mariani A, Veronesi F (1991) Cytological analysis of macro- and microsporogenesis of a diploid alfalfa clone producing male and female 2n gametes. Crop Sci 31:1258–1263Google Scholar
  17. Veronesi F, Tavoletti S, Mariani A (1990) Identification of 2n and 4n gamete producers in an experimental population of diploid Medicago. J Genet Breed 44:143–148Google Scholar
  18. Watanabe K, Peloquin SJ, Endo M (1991) Genetic significance of mode of polyploidization: somatic doubling or 2n gametes? Genome 34:28–34Google Scholar

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • A. Mariani
    • 1
  • S. Tavoletti
    • 2
  • F. Veronesi
    • 2
  1. 1.Istituto di Ricerche sul Miglioramento Genetico delle Plante Foraggere, C.N.R.PerugiaItaly
  2. 2.Dipartimento di Biotecnologie Agrarie e Ambientali, Facoltá di AgrariaUniversitá degli Studi di AnconaAnconaItaly

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