Summary
Mature pollen of Phoenix dactylifera was freeze-fractured in germination medium. The surface of the generative cell was highly convoluted. Microtubules were not in close contact with the indentations. The vegetative cell membrane was appressed to the generative cell. Ordered ridges appeared in both fracture faces of the vegetative cell inner plasma membrane at the indentations. No ordered ridges were observed in the fracture faces of the generative cell. The nuclear envelopes of the vegetative and generative cells differed, with the generative cell having fewer and larger nuclear pores irregularly dispersed among porefree areas. These differences in plasma membrane and in nuclear envelope correlate with the subsequent differentiation of the two cells.
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Branton D, Bullivant S, Gilula NB, Karnovsky MJ, Moor H, Muhlethaler K, Northcote DH, Packer L, Satir B, Satir P, Speth V, Stahelin LA, Steere RL, Weinstein RS (1975) Freeze-etching nomenclature. Science 190:54–56
Crevecoeur M, Deltour R, Bronchart R (1982) Quantitative freeze-fracture study of plasma membrane and nuclear envelope of Zea mays root cells during early germination. J Ultrastruct Res 80:1–11
Cresti M, Ciampolini F, Kapil RN (1984) Generative cells of some angiosperms with particular emphasis on their microtubules. J Submicrosc Cytol 16:317–326
Cresti M, Lancelle SA, Hepler PK (1987) Structure of the generative cell wall complex after freeze substitution in the pollen tubes of Nicotiana and Impatiens. J Cell Sci 88:373–378
DeMason DA, Chandra Sekhar KN (1988) The breeding system in the date palm (Phoenix dactylifera) and its recognition by early cultivators. Adv Econ Bot 6:20–35
Friend DS (1982) Plasma-membrane diversity in a highly polarized cell. J Cell Biol 93:243–249
Friend DS, Fawcett DW (1974) Membrane differentiations in freeze-fractured mammalian sperm. J Cell Biol 63:641–664
Gilula NB (1974) Junctions between cells. In: Cox RP (ed) Cell communication. Wiley, New York, pp 1–29
Lott JNA, Vollmer CM (1975) Changes in the cotyledons of Cucurbita maxima during germination. J Ultrastruct Res 852:156–166
Maul GG, Price JW, Lieberman MW (1971) Formation and distribution of nuclear pore complexes in interphase. J Cell Biol 51:405–418
McCoy K, Knox RB (1988) The plasma membrane and generative cell organization in pollen of the mimosoid legume, Acacia retinodes. Protoplasma 143:85–92
Mepham RH, Lane GR (1969) Nucleopores and polyribosome formation. Nature 221:288–289
Myles DG, Southworth D, Hepler PK (1978) A freeze-fracture study of the nuclear envelope during spermiogenesis in Marsilea. Formation of a pore-free zone associated with the microtubule ribbon. Protoplasma 93:419–431
Platt-Aloia KA, Lord EM, DeMason DA, Thomson WW (1986) Freeze-fracture observations on membranes of dry and hydrated pollen from Collomia, Phoenix and Zea. Planta 168:291–298
Severs NJ, Jordan EG, Williamson DH (1976) Nuclear pore absence from areas of close association between nucleus and vacuole in synchronous yeast cultures. J Ultrastruct Res 54:374–387
Southworth D, Platt-Aloia KA, Thomson WW (1989) Freeze fracture of the generative cell of Phoenix dactylifera and sperm cells of Zea mays and Gerbera jamesonii. Am J Bot 76:70
Zasadzinski JAN, Schneider MB (1987) Ripple effect, amplitude, and configuration in lyotropic liquid crystals as a function of effective head group size. J Phys (Paris) 48:2001–2011
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Acknowledgements. We thank J.I. Stillman for technical assistance with the thin section preparations. This research was supported in part by NSF grant DCB-8607765 to W.W.T.
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Southworth, D., Platt-Aloia, K.A., DeMason, D.A. et al. Freeze-fracture of the generative cell of Phoenix dactylifera (Arecaceae). Sexual Plant Reprod 2, 270–276 (1989). https://doi.org/10.1007/BF00195587
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DOI: https://doi.org/10.1007/BF00195587