Spore age and sterilization affects germination and early gametophyte development of Platycerium bifurcatum

The effects of spore age and sterilization on spore germination and early g ametophyte development were investigated in the fern, Platycerium bifurcatu m. The highest germination percentage of sterilized spores was obtained wit h 2-3 month old spores. Further increase in spore age leads to a decline in germination and primary rhizoid initiation. In contrast, spore age had no effect on the germination of unsterilized spores, where maximum response wa s observed with spores of both storage periods tested, 2 and 14 months. Inc reasing spore age delays early gametophyte development. In cultures of ster ilized spores, this was evident from both a decrease in the length of the p rimary rhizoid and the decreased number of rhizoids and cells per gametophy te. Although longer primary rhizoids developed from unsterilized spores of both ages, after 10 days other growth parameters of gametophytes were simil ar or even lower compared to those from sterilized spores.