In Vitro Spore Culture of the Endangered Lecanopteris deparioides (Polypodiaceae) Using Modified Culture Media

Lecanopteris deparioides (Cesati) Baker is an endangered epiphytic fern found in Java, Western Malesia, and the Philippines. An important strategy for the conservation of this endangered fern is in vitro culture utilizing spores. This study was conducted on this species to examine the spore morphology, mass-propagate using spores sown in six modified culture media – namely T1 (anonotong), T2 (anonotong + garden soil), T3 (anonotong + grounded clay pots), T4 (garden soil + cocopeat), T5 (grounded clay pots + garden soil), and T6 (anonotong + cocopeat) – and document the reproductive biology. Fertile fronds bore sporangia each with 62–64 spores, which were yellow, biconvex, and monolete. The average spore size was 44.7 x 36.8 μm. Fresh spores were sown in different modified media under specific laboratory conditions. One hundred percent spore germination was observed (100%) in all treatments but varied in days to germinate as early as 4 d after sowing (DAS) in T2, T3, and T5 and 100% in all media after 16 d of culture. Spore germination is of Gleichenia-type, whereas gametophyte development is of the Drynaria-type. The adult gametophyte was of cordate-thalloid form, and the gametangia were of the advanced leptosporangiate type. Funnel-shaped antheridia were first developed between 24–39 DAS, which produced 32 spermatozoids, whereas archegonia appeared 37–66 DAS. Gametophytes began to sexually produce sporophytes 66–99 DAS. Out of the six treatments, T1 and T2 showed positive results for faster growth producing bigger gametophytes, whereas both T3 and T5 have positive responses for development given the faster formation of each developmental stage. Results of this study suggest that in vitro culture utilizing spores in modified media composed of garden soil, grounded clay pots, and anonotong is the best technique for conserving this rare fern.