Hubungan Genetik Empat Populasi Kelapa Genjah Berdasarkan Penanda RAPD ( Random Amplified Polymorphic DNA )

Abstract

Genetic relationships among 4 dwarf coconut populations [Genjah Hijau Jombang (Gill), GeniahRaja (GRA), Genjah Hijau Nias (GHN), Genjah Malabar (GMB)] bad been evaluated based on RAPD markers. Ten trees from each coconut populations were chosen, and their leaf DNA's were amplified using 9 primers (selected from 35 random deeamer primers) in PCR thermed cycler machine. A total of 108 RAPD bands were recorded, and 83 of them were polimorphic (77 %). Unweighted Pair-Group Method Arithmetic (UPGMA) was applied to RAPD binary data matrix using Numerical Taxonomy and Multivariate System (NTSYS) version 1.8 computer program, showed dwarf coconut trees were grouped within their populations. Genetic similarity of dwarf coconuts within GRA population was the most closely related compared to those within other populations. Closely geographical distance ofdwarfcoconut origin did not make their genetic ralationships closer. RAPD data did not support that the same fruit nut color bad to have more genetically similar. The Principle Component Analysis ofRAPD binary data matrix showed dwarf coconut populations grouped in four different quadrants. OPB-08350 RAPD band could be used as a specific genetic markers for GRA coconut populations. While OPA-082500,OPA-Q81250, and OPC-QS550 RAPD band can be used to distinguish Gill or GMB from GRA and GHN coconuts. OPA-13300 RAPD band had been identified and found only in GRA and GMB coconut populations.

Evaluasi hubungan genetik telah diIa1rukan pada 40 individu dari 4 populasi kelapa geniah, yaitu Genjah Hijau Jombang (GIll), Genjah Raja (GRA), Genjah Hijau Nias (GHN), dan Genjah Malabar (GMB) menggunakan penanda RAPD. Dati 9 primer acak 10-mer yangdigunakan (diseleksi dari 35 primer acak decamer) dihasilkan 108 pita dan 77 % diantaranya merupakan pita polimorfik. Jumlah pita berkisarantara 7 dan 15 pita per primer yang berukuran antara 250 2500 pb, Berdasarkan analisis data biller dari pita RAPD dengan metode UPGMA (Unweighted Pair-Group Method Arithmetic) melalui program NTSYS (Numericai Taxonomy and Multivariate System) versi 1.80, menunjukkan bahwa individu pohon kelapa Genjah mengelompok kedalam populasinya masingmasing. Kemiripan genetik pohon kelapa di daIam populasi GRA relatif lebih dekat dibandingkan di dalam populasi lainnya. Hubungan genetik kelapa antar populasi GHN dan GMB relatif lebih dekat dibandingkan terhadap GID atau GRA Kedekatan jarak geografi tempat asal populasi kelapa Genjah dan kesamaan wama buah tidak menjamin kedekatan hubungan genetik antar populasi kelapa Genjah berdasarkan penanda RAPD. Analisis komponen utama, berhasil melacak pita yang berperan dalam mengelompokkan keempat populasi kelapa Genjah. Pita RAPD OPA-082500, OPA-08125o dan OPC-05550 dapat digunakan untuk membedakan populasi kelapa GID atau GMB dari kelapa GRA dan GHN, sedangkan pita OPA-1330o membedakan populasi kelapa GRA atau GMB dati kelapa GID dan GHN. Pita RAPD OPB-08350 dapat digunakan sebagai penanda populasi kelapa GRA yang membedakannya dati ketiga populasi kelapa lainnya