Electronic Theses and Dissertation

Paku tiang, cyathea contaminans (wall. ex hook.) copel. merupakan salah satu jenis paku pohon komoditas ekspor indonesia karena mempunyai nilai guna tinggi. pemanfaatan c. contaminans saat ini masih mengandalkan hasil panen dari alam, oleh karena itu perdagangannya diatur secara internasional dalam apendiks ii cites. pengeskploitasian c. contaminans yang berlebihan di habitat aslinya dapat menyebabkan penurunan populasi, sehingga diperlukan upaya konservasi untuk mencegah kepunahannya. salah satu usaha konservasi tersebut adalah dengan memperlajari aspek-aspek perbanyakannya. kultur spora in vitro merupakan salah satu cara yang tepat untuk memenuhi kebutuhan bibit secara massal guna keperluan domestiksasi maupun reintroduksi paku pohon. salah satu langkah penting dalam kultur spora in vitro untuk menginduksi pembentukan sporofit adalah subkultur massa gametofit. massa gametofit (protalus) dewasa yang telah terbentuk dari hasil penyemaian spora, diinduksi dengan cara mensubkultur massa gametofit pada kombinasi konsentrasi media murashige & skoog (ms), kepadatan populasi gametofit, dan metode pemberian air atau tidak diberi air. penelitian ini menggunakan rancangan acak lengkap pola faktorial (ral faktorial) yang terdiri dari kombinasi 3 taraf perlakuan dan 5 ulangan. faktor pertama konsentrasi media (1/4, 1/8, dan 1/12 ms), faktor kedua kepadatan populasi tanam (1, 2, dan 3 gametofit/botol), faktor ketiga metode pemberian air (diberi 1 ml air steril dan tanpa 1 ml air steril). penelitian dilaksanakan di laboratorium kultur jaringan, pusat riset konservasi tumbuhan kebun raya dan kehutanan, organisasi riset hayati dan lingkungan – brin, bogor. parameter yang diamati yaitu diameter massa gametofit, jumlah sporofit, dan waktu muncul sporofit. hasil penelitian menunjukkan pertambahan diameter massa gametofit c contaminans terbaik terdapat pada perlakuan 1/4 ms + 2 gametofit/botol + tanpa 1 ml air dengan rerata 2,14 cm tetapi tidak berbeda nyata dengan perlakuan lainnya kecuali pada perlakuan 1/12 ms + 3 gametofit/botol + 1 ml air dengan rerata 1,45 cm. jumlah sporofit c. contaminans terbanyak terdapat pada perlakuan 1/4 ms + 3 gametofit/botol + 1 ml air dengan total pertumbuhan 23 sporofit tetapi tidak berbeda nyata dengan perlakuan lainnya kecuali pada perlakuan 1/4 ms + 1 gametofit/botol + tanpa 1 ml air dan 1/12 ms + 1 gametofit/botol + tanpa 1 ml air dengan total pertumbuhan 0 sporofit. pertumbuhan sporofit c. contaminans pertama kali diperoleh pada media 1/8 ms + 1 gametofit/botol + 1 ml air pada 8 mst disusul perlakuan 1/4 ms + 2 gametofit/botol + 1 ml air dan 1/4 ms + 3 gametofit/botol + 1 ml air pada 9 mst. kata kunci : cyathea contaminans, murashige & skoog (ms), kepadatan tanam, massa protalus, gametofit, sporofit.

Paku Tiang, Cyathea contaminans (Wall. Ex Hook.) Copel., is one of the Indonesian tree ferns that is exported as a commodity due to its high utility value. C. contaminans is internationally controlled under CITES Appendix II, as its current use depends solely on the collection of natural resources. The further exploitation of C. contaminans in its native range may have a negative impact on its population, and conservation initiatives are needed to prevent it from becoming endangered. One conservation effort is the study of aspects of tree fern propagation. In vitro spore culture is an appropriate method for efficiently producing large numbers of seedlings for the purpose of domestication and reintroduction. A crucial step in in vitro spore culture is subculturing the gametophyte mass, which induces sporophyte formation. The prothallus, which is the mature gametophyte mass, is produced through spore seeding. This can be stimulated by subculturing the gametophyte mass using a combination of Murashige & Skoog (MS) media concentration, gametophyte population density, and the addition of water or without water. A Completely Randomised Design (CRD) factorial pattern comprising a combination of 3 treatment levels and 5 replicates was used in this study. The study investigated three independent factors, the first is media concentration (1/4, 1/8, and 1/12 MS), the second is plant population density (1, 2, and 3 gametophytes/bottle), and the third is water application method (with 1 mL sterile water and without 1 mL sterile water). The studies were made at the Tissue Culture Laboratory, Research Centre for Plant Conservation of Botanical Gardens and Forestry, Biological and Environmental Research Organisation - BRIN, Bogor. The parameters measured were the diameter of the gametophyte mass, the number of sporophytes, and the time when the sporophytes formed. The results showed that the best diameter growth of C. contaminans gametophyte mass was found in the treatment of 1/4 MS + 2 gametophytes/bottle + without 1 mL of water with an average of 2.14 cm, but not significantly different from other treatments except in the treatment of 1/12 MS + 3 gametophytes/bottle + 1 mL of water with an average of 1.45 cm. The treatment of 1/4 MS + 3 gametophytes per bottle + 1 mL of water had the most number of C. contaminans sporophytes with a total growth of 23 sporophytes but was not significantly different from the other treatments except for 1/4 MS + 1 gametophyte per bottle + no 1 mL of water and 1/12 MS + 1 gametophyte per bottle + no 1 mL of water with a total growth of 0 sporophytes. The first growth of C. contaminans sporophytes was obtained on 1/8 MS + 1 gametophyte/bottle + 1 mL of water at 8 weeks after planting, followed by 1/4 MS + 2 gametophytes/bottle + 1 mL of water and 1/4 MS + 3 gametophytes/bottle + 1 mL of water at 9 weeks after planting. Keywords: Cyathea contaminans, Murashige & Skoog (MS), planting density, prothallus mass, gametophytes, sporophytes.