Abstract

NAZARIO-GALINDO, Alejandra  and  ARREGUIN-SANCHEZ, María de la Luz. DESCRIPCIÓN DEL DESARROLLO DEL GAMETOFITO Y PRIMERAS FASES DEL ESPOROFITO DE POLYSTICHUM ORDINATUM (KUNZE) LIEBM. (DRYOPTERIDACEAE-PTERIDOPHYTA). Polibotánica [online]. 2007, n.24, pp.139-152. ISSN 1405-2768.

ABSTRACT

This study examined the life cycle of Polystichum ordinatum (Kunze) Liebm. Specimens were collected at Cuetzalan, Puebla, Mexico. The spores were sown according to the technique of Montoya-Casimiro et al. (2000). The germination pattern was of the Vittaria type, and prothallial development was of the Aspidium type. Two types of gametophyte were found: cordate with only archegonia and elongated with antheridia. In the latter type of gametophyte antheridia developed in four different positions: a) in the middle part, b) in a proximal central position, c) over the whole surface and, d) along the margin of the gametophyte. Trichomes were observed in cordate and elongated gametophytes; only gametophytes with marginal antheridia were glabrous. Young sporophytes were obtained around 325 days after sowing. The life cycle of P. ordinatum is like that of Equisetum, having the same kind of spores, exosporic gametophytes and unisexual gametophytes.

Keywords : Polystichum ordinatum; gametophyte; sporophyte; pteridophyta; Puebla.

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