The ontogeny of the sporophyte in Dryopteris wallichiana (Spreng.) Hyl.

NARVÁEZ, P.L; MARTÍNEZ, O.G.

Tafí del Valle,Tucumán

Jornada; 19º Jornadas Científicas de la Asociación de Biología de Tucumán; 2002

Asocación de Biología de Tucumán

Dryopteris wallichiana grows in the Northwest parto of Argentina, mainly in montane forests at high elevations, 1000-3000 m. It is terrestrial and prefers humid slopes. An account on the ontogeny of the sporophyte is given. The spores were collected from plants in Quebrada de San Lorenzo (Salta) and the samples were donated to the MCNS herbarium. Sporophytes were obtained through spore culture in two nutrient media: Knudson and Murashige. Young sporophytes were moved to pots containing soil and sand (3:1). For anatomic studies, the sections of 10-12ì were coloured with ferric hematoxylin of Heidenhein. The Foster’s technique was used for diaphanization. Mature gametophytes were formed two months after culture, 30 days later began the formation of the midrib near the notch. Tissue differentiation was immediate, producing the sporophyte. The sporophyte is apogamic, bears only antheridia, and the development follows this sequence: leaf, root and finally the stem. Theleaf, first lobulated, undergoes several divisions until the characteristic pinnate-pinnatifid blade is formed; it has open nervation and the indumentum is composed of scales.