RESUMO
Macrothelypteris torresiana is a terrestrial fern belongs to the family Thelypteridaceae. It is very imperative to know the germination and growth pattern of this fern to make strategy for ex- situ conservation. In the present study germination of spore, developmental pattern of prothallium with particular emphasis on emergence of antheridia as well as archegonia, their fertilization and development of sporophytes were studied. The spores were spheroidal or reniform with broadly winged fimbriate perispore having average size of 48 ± 3.6 × 39 ± 4.2 µm. The spores started germinating just after 6 days of plating and percentage of germination was 94%. The germination pattern of spore was Vittaria type and development of gametophyte was Aspidium type. After 27 days of plating, a very distinct cordate-shaped adult gametophyte with deep apical notch and unicellular papillate hairs throughout the gametophyte was developed. The rhizoids appeared away from the apical notch of the gametophyte. The gametophyte first developed archegonia on 32nd day, whereas antheridia were developed on 42nd day. In isolate culture the gametophytes did not develop any sporophyte whereas in composite culture juvenile sporophytes were emerged on 77th day. This suggests the plant has ability to reproduce only through inter-gametophytic selfing and crossing, hence decreasing the plant's capacity for colonization in a particular locality.
