Keragaman Delapan Anggrek Dendrobium spp. Indonesia Berdasarkan Penanda RAPD

DHARMESTA ADHIWIRA, Dr. Ir. Aziz Purwantoro, M.Sc.

2013 | Skripsi | PEMULIAAN TANAMAN

Keragaman di antara tanaman anggrek Dendrobium spp. perlu diketahui untuk melakukan persilangan dalam program pemuliaan tanaman anggrek. Persilangan antara anggrek Dendrobium spp. yang mempunyai kemiripan akan meningkatkan peluang keberhasilan persilangan. Penelitian ini bertujuan untuk menentukan tingkat kemiripan dan jarak genetik di antara anggrek Dendrobium spp. Indonesia berdasarkan pola pita DNA. Tingkat kemiripan 10 genotipe anggrek dianalisis menggunakan 85 pita DNA yang diperoleh dari hasil amplifikasi lima primer acak RAPD (OPA2, OPA4, OPA7, OPA9 dan OPA10). Hasil penelitian menunjukkan adanya keragaman genetik yang diindikasikan dari persentase lokus polimorfik dalam kisaran 11,76 – 40%. Hasil analisis kluster berdasarkan penanda molekuler menunjukkan bahwa anggrek Dendrobium terbagi menjadi enam kelompok pada dendogram antar populasi dengan jarak 7,5 yaitu: (1) D. spectabile dan D. macrophyllum, (2) D. lasianthera, (3) D. antennatum, D. discolor dan D. stratiotes, (4) D. smillieae dan D. crumenatum, (5) D. signatum, dan (6) D. fimbriatum. Dua spesies Dendrobium yang berasal dari luar Indonesia (D. fimbriatum dan D. signatum) membentuk kelompok sendiri di luar kedelapan Dendrobium asli Indonesia, menandakan bahwa kedua spesies tersebut memiliki kemiripan yang jauh dengan Dendrobium asli Indonesia. Hasil pengelompokan berdasarkan penanda RAPD berbeda dengan hasil pengelompokan berdasarkan pengamatan morfologi, karena adanya interaksi lingkungan.

Study on diversity among eight Dendrobium spp. orchids is necessary for orchid breeders in order to plant crossing efficiency. Highly similarity among Dendrobium spp. would increase crossing opportunity. The objectives of this study were to grouping orchid genotypes into clusters according to their similarity as measured by DNA banding patterns. Genetic similarity among 10 orchid genotypes were analysed based on 85 bands generated from five RAPD primers. The result showed that genetic diversity within species indicated by percentage of polymorphic loci was in range of 11.76 to 40%. Cluster analysis based on molecular markers showed that the Dendrobiums were divided into six groups at a distance of 7.5 in dendogram, where is first group consisted of D. spectabile and D. macrophyllum, second group consisted of D. lasianthera, third group consisted of D. antennatum, D. discolor, and D. stratiotes, fourth group consisted of D. smillieae and D. crumenatum, fifth group consisted of D. signatum, and sixth group consisted of D. fimbriatum. Two Dendrobium spesies from another country (D. fimbriatum and D. signatum) made a group outside of Dendrobium of Indonesia’s group, indicating that both spesies have distant genetic similarity with Dendrobium spesies of Indonesia. Result of grouping based on molecular markers is different from grouping based on morphological observation, probably due to environment effects.

Kata Kunci : anggrek, Dendrobium, keragaman genetik, RAPD, tingkat kemiripan