Summary
If anthers of Datura innoxia containing microspores are cultured at 28° C for 24 h, two forms of haploid pollen grains are produced; one with typical unequal generative and vegetative nuclei (A), and the other with equal vegetativetype nuclei (B). The A form predominates. After 24 to 72 h in culture, three embryogenic events ensue; 1) division of the vegetative cell in A grains accompanied by rapid degeneration of the generative cell, 2) simultaneous or independent mitosis of the nuclei in B grains, and 3) simultaneous mitosis of both the generative and vegetative nuclei in A grains following two successive cycles of DNA synthesis in the generative nucleus, but only one in the vegetative nucleus (C). The endoreduplicated generative nucleus gives rise to diplochromosomes which it is postulated divide on a common spindle together with the vegetative chromosomes to yield a 3n proembryoid. In other C grains, simultaneous mitosis of an endoreduplicated generative nucleus and two vegetative daughter nuclei can occur. Nuclear fusion in these grains is envisaged as leading to a 4n proembryoid. Diploid proembryoids probably arise by nuclear fusion in A or B grains. At plantlet emergence, mainly n and 2n plantlets are obtained. Higher ploidy proembryoids fail to develop probably as a result of competitive influences.
Similar embryogenic events occur in cultures initiated at the stages of the first pollen mitosis and young pollen grains, but C embryogenesis predominates. Competition from lower ploidy embryoids is minimised and 3n, 4n and even 6n plantlets are obtained.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Blakeslee, A. F., Avery, A. G.: Three genes located in the 21.22 chromosome of the Jimson weed. J. Hered. 25, 393–404 (1934)
Bourgin, J. P., Nitsch, J. P.: Obtention de Nicotiana haploides à partir d'étamines cultivées in vitro. Ann. Physiol vég. 9, 377–382 (1967)
Collins, G. B., Legg, P. D., Kasperbauer, M. T.: Chromosome numbers in anther derived haploids of two Nicotiana species. J. Hered. 63, 113–118 (1972)
Dunwell, J. M., Perry, E.: Influence of in vivo growth conditions of N. tabacum plants on the in vitro embryogenic potential of their anthers. In: John Innes Annual Report No. 64 (1973)
Engvild, K. C.: Triploid petunias from anther cultures. Hereditas (Lund.) 74, 144–147 (1973)
Engvild, K. C., Linde-Laursen, I., Lundqvist, A.: Anther cultures of Datura innoxia: flower bud stage and embryoid level of ploidy. Hereditas (Lund.) 72, 331–332 (1972)
Guha, S., Maheshwari, S. C.: Development of embryoids from pollen grains of Datura in vitro. Phytomorphology 17, 454–461 (1967)
Harn, C.: Studies on anther culture in Solanum nigrum. In: SABRAO Newsletter 3, 39–42 (1971)
Iyer, R. D., Raina, S. K.: The early ontogeny of embryoids and callus from pollen and subsequent organogenesis in anther cultures of Datura metel and rice. Planta (Berl.) 104, 146–156 (1972)
Narayanaswamy, S., Chandy, L. P.: In vitro production of haploid, diploid and triploid androgenic embryoids and plantlets in Datura metel L. Ann. Bot. 35, 535–542 (1971)
Narayanaswamy, S., George, L.: Morphogenesis of Belladonna (Atropa belladonna) L. plantlets from pollen in culture. Ind. J. exp. Biol. 10, 382–384 (1972)
Niizeki, H., Oono, K.: Rice plants obtained by anther culture. In: Les cultures de tissus de Plantes, p. 251–257, Colloques Internationaux du C.N.R.S. No. 193. Paris 1971
Nishi, I., Mitsuoka, S.: Occurrence of various ploidy plants from anther and ovary culture of rice plant. Jap. J. Genet. 44, 341–346 (1969)
Nitsch, C., Noreel, B.: Effet d'un choc thermique sur le pouvoir embryogène du pollen de Datura innoxia cultivé dans l'anthère ou isolé de l'anthère. C.R.Acad. Sci. (Paris) 276, 303–306 (1973)
Nitsch, J. P., Nitsch, C.: Obtention de plantes haploides à partir de pollen. Bull Soc. bot. Fr. 117, 339–360 (1970)
Noreel, B.: Etude cytologique de l'androgénèse expérimentale chez Nicotiana tabacum et Datura innoxia. Bull. Soc. bot. Fr. 117, 461–478 (1970)
Raquin, C., Pilet, V.: Production de plantules à partir d'anthères de Pétunias cultivées in vitro. C.R. Acad. Sci. (Paris) 274, 1019–1022 (1972)
Roland, F.: Characterization and extraction of the polysaccharides of the intine and of the generative cell wall in the pollen grains of some Ranunculaceae. Grana 11, 101–106 (1971)
Satina, S., Balkeslee, A. F.: Cytological effects of a gene in Datura which causes dyad formation in sporogenesis. Bot. Gaz. 96, 521–523 (1935)
Sunderland, N.: Pollen plants and their significance. New Scientist 47, 142–144 (1970)
Sunderland, N.: Anther culture: a progress report. Sci. Progr. Oxford 59, 527–549 (1971)
Sunderland, N.: Pollen and anther culture. In: Plant tissue and cell culture, p. 205–239 (H. E. Street ed.) Oxford: Blackwell 1973
Sunderland, N., Wicks, F. M.: Embryoid formation in pollen grains of Nicotiana tabacum. J. exp. Bot. 22, 213–226 (1971)
Zenkteler, M.: In vitro production of haploid plants from pollen grains of Atropa belladonna L. Experientia (Basel) 27, 1087 (1971)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sunderland, N., Collins, G.B. & Dunwell, J.M. The role of nuclear fusion in pollen embryogenesis of Datura innoxia Mill.. Planta 117, 227–241 (1974). https://doi.org/10.1007/BF00388396
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00388396