Keywords
ferns
germination
scanning electron microscope
sexual phase
spore.
desarrollo
espora
fase sexual
germinación
helechos
microscopio electrónico de barrido
How to Cite
Abstract
Acrostichum is a pantropical genus and has four species, two of which occur in the Neotropics, A. aureum and A. danaeifolium. In Mexico, A. danaeifolium grows further in land wet soils and is much more common than A. aureum, which is typically found in brackish or saline habitats near the coast, and is restricted to coastal saline mangrove communities. The purpose of this paper was to describe and compare the morphogenesis of the sexual phase of A. aureum and A. danaeifolium for systematic purposes. For this, spores of each species were sown in Petri dishes with agar, previously enriched with sterilized Thompson's medium. To avoid contamination and dehydration, the dishes were kept in transparent plastic bags under laboratory conditions. For the micro-morphological observation with SEM, the gametophyte development phases were fixed in FAA with 0.8 % sucrose for 24 h. Photomicrographs of spores, development stages of gametophytes and young sporophytes were observed with scanning electron microscope Jeol JSM5310-LV. Our results showed that the spores of both species are triletes, globose and positive photoblastic. Germination is Vittaria-type; the germinate filaments are short and uniseriate (5 to 7 cells), and prothallial development is Ceratopteris-type. The adult gametophytes of both species have asymmetrical wings. Adult gametophytes in culture are cordiform-spatulate. Antheridia have a broad basal cell, an annular cell, and an asymmetric opercular cell. Archegonia have short necks and four triangular cells at the mouth of the neck. The first leaf of the sporophyte is lobed, with dichotomous veins and anomocytic stomata. The gemmae are formed in adult gametophytes in both species. The development of the gametophyte of A. aureum, A. danaeifolium and A. speciosum share many similarities such as the development of a lateral meristem, asymmetric nature of the mature prothallus, lack of hairs on the prothallus, and undivided asymmetrical opercular antheridia morphology. The genus Acrostichum is the sister group of Ceratopteris, another genus of aquatic ferns; they differ in the antheridium morphology, Acrostichum has an asymmetric opercular cell and Ceratopteris shows an undivided cap cell, but the notable difference is the sporophyte morphology.References
Adams, S., & Tomlinson, P. B. (1979). Acrostichum in Florida. American Fern Journal, 69, 42-46.
Bozzola, J. J. & Russell, L. D. (1998). Electron microscopy: principles and techniques for Biologists. London, England: Jones y Bartlett Publishers.
Dettmann, M. E., & Clifford, H. T. (1991). Spore morphology of Anemia, Mohria, and Ceratopteris (Filicales). American Journal of Botany, 78, 303-325.
Eakle, T. W. (1975). Photoperiodic control of spore germination of Acrostichum aureum. American Fern Journal, 65, 94-95.
Erdtman, G. (1971). Pollen and spore morphology. Plant taxonomy. Stockholm, Almqvist & Wiksell, New York: Ronald Press Co.
García de López, I. (1978). Revisión del género Acrostichum en la República Dominicana. Moscosoa, 1, 64-70.
Gastony, G. J., & Rollo, D. R. (1995). Phylogeny and generic circumscriptions of cheilanthoid ferns (Pteridaceae: Cheilanhoideae) inferrer from rbcL nucleotide sequences. American Fern Journal, 85, 341-360.
Gastony, G. J., & Rollo, D. R. (1998). Cheilanthoid fern (Pteridaceae: Cheilanthoideae) in the southwestern United States and adjacent Mexico- a molecular phylogenetic reassessment of generic lines. Aliso, 17, 131-144.
Hasebe, M., Wolf, P. G., Pryer, K. M., Ueda, K., Ito, M., Sano, R., Gastony, G. J., Yokoyama, J., Manhart, J. R., Murakami, N., Crane, E. H., Haufler, C. H., & Hauk, W. D. (1995 [1996]). Fern phylogeny based on rbcL nucleotide sequences. American Fern Journal, 85, 134-181.
Klekowski, E. J. Jr. (1969). Reproductive biology of the Pteridophyta III: a study of the Blechnaceae. Botanical journal of the Linnean Society. London, 62, 361-377.
Kshirsagar, M. K., & Mehta, A. R. (1979). In vitro studies of the life cycle of Acrostichum aureum L. In S. S. Bir (Ed.), Recent Researches in Plants Sciences (pp. 71-73). New Delhi: Kalyani Publ.
Kubitzki, K. (1990). The families and genera of vascular plants. New York: Springer-Verlag.
León, B. (1990). New localities for Acrostichum danaeifolium in Peru. American Fern Journal, 80, 113-114.
Li, X.-P., & Ong, B.-L. (1997a). Ultrastructural changes in gametophytes of Acrostichum aureum L. cultured in different sodium chloride concentrations. Biologia Plantarum, 39, 607-614.
Li, X.-P., & Ong, B.-L. (1997b). Tolerance of gametophytes of Acrostichum aureum (L.) to salinity and water stress. Photosynthetica, 34, 21-30.
Li, X.-P., & Ong, B.-L. (1998). Responses of the photosynthesis to NaCl in gametophytes of Acrostichum aureum. Physiologia Plantarum, 102, 119-127.
Lloyd, R. M. (1980). Reproductive biology and gametophyte morphology of New World populations of Acrostichum aureum. American Fern Journal, 70, 99-110.
Lloyd, R. M., & Buckley, D. P. (1986). Effects of salinity on gametophyte growth of Acrostichum aureum and A. danaeifolium. Fern Gazette, 13, 97-103.
Lloyd, R. M., & Gregg, T. L. (1975). Reproductive biology and gametophyte morphology of Acrostichum danaeifolium from Mexico. American Fern Journal, 65, 105-120.
Mendoza-Ruiz, A. (2001). Morfogénesis de la fase sexual de pteridofitas mexicanas, familia Dryopteridaceae. (Tesis de Maestría) Universidad Nacional Autónoma de México, México, D. F., México.
Mickel, J. T., & Smith, A. R. (2004). The Pteridophytes of Mexico. Memoirs of the New York Botanical Garden. New York, USA: The New York Botanical Garden.
Moran, R. C. (1995). 1. Acrostichum L. In: R. C. Moran., & R, Riba. (Eds.), Flora Mesoamericana. Vol. 1, Psilotaceae a Salviniaceae (pp. 105-106). México: Universidad Nacional Autónoma de México (Instituto de Biología) Missouri Botanical Garden & The Natural History Museum (London).
Nayar, B. K., & Kaur, S. (1969). Types of prothallial development in homosporous ferns. Phytomorphology, 19, 179-188.
Nayar, B. K., & Kaur, S. (1971). Gametophytes of homosporous ferns. The Botanical Review, 37, 295-396.
Nayar, B. K., & Kazmi, F. (1964). The gametophyte of Acrostichum aureum L. Procceding Indian Academy of Science, 59, 185-194.
PPG I (Pteridophyte Phylogeny Group). (2016). A community-derived classification for extant lycophytes and ferns. Journal of Systematics and Evolution, 54, 563-603.
Prado, J., Del Nero Rodrígues, C., Salatino, A., & Salatino, M. L. F. (2007). Phylogenetic relationships among Pteridaceae, including Brazilian species, inferred from rbcL sequences. Taxon, 56, 355-368.
Pryer, K. M., Smith, A. R., & Skog, J. E. (1995). Phylogenetic relationship of extant ferns based on evidence from morphology and rbcL sequences. American Fern Journal, 85, 205-282.
Schuettpelz, E., & Pryer, K. M. (2007). Fern phylogeny inferred from 400 leptosporangiate species and three plastid genes. Taxon, 56, 1037-1050.
Schuettpelz, E., Schneider, H., Huiet, L., Windham, M. D., & Pryer, K. M. (2007). A molecular phylogeny of the fern family Pteridaceae: Assessing overall relationships and the affinities of previously unsampled genera. Molecular Phylogenetics and Evolution, 44, 1172-1185.
Schumann, E. (1915). Die Acrosticheen und ihre stellung im System der Farne. Flora, 108, 210-260.
Smith, A. R., Pryer, V. E., Schuettpelz, E., Korall, H., Schneider, H., & Wolf, P. G. (2006). A classification for extant ferns. Taxon, 55, 705-731.
Stokey, A. G., & Atkinson, L. R. (1952). The gametophyte of Acrostichum speciosum Willd. Phytomorphology, 2, 105-113.
Sun, W.-Q., Li, X.-P., & Ong, B.-L. (1999). Preferential accumulation of D-pinitol in Acrostichum aureum gametophytes in response to salt stress. Physiologia Plantarum, 105, 51-57.
Tryon, A. F., & Lugardon, B. (1992). Spore of the Pteridophyta. New York: Springer-Verlag.
Tryon, R. M., & Tryon, A. F. (1982). Fern and allied plants. New York: Springer-Verlag.
Van Cotthem, W. R. J. (1984). Stomatal types and systematics, In: A. C. Jermy., J. A. Crabbe., & B. A. Thomas. (Eds.). The phylogeny and classification of the ferns (pp. 59-71). Germany: Academic Press Inc.
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