VARIASI MORFOLOGIS DAN GENETIKKACANG KOMAK (Lablab purpureus (L.) Sweet )DI LOMBOK, NUSA TENGGARA BARAT

Ervina Titi Jayanti, Dr. Rina sri Kasiamdari

2011 | Tesis | S2 Biologi

Kacang komak (Lablab purpureus (L.) Sweet) merupakan anggota Fabaceae yang umum dibudidayakan di Pulau Lombok. Selama ini penelitian mengenai kacang komak di Indonesia masih sangat kurang dan hanya terfokus pada kandungan biokimia dan fungsinya sebagai isolat protein. PeneIitian yang mengkaji variasi morfologis dan molekular kacang komak di Indonesia khususnya P. Lombok, NTB belum pemah dilakukan. Penelitian ini bertujuan untuk mempelajari keragaman morfologis dan genetik plasma nutfah kacang komak yang di Lombok, NTB serta hubungan fenetik yang ada diantaranya. Penelitian dilakukan di 4 kabupaten (Lombok Barat, Lombok Tengah, Lombok Timur, dan Lombok Utara) yang ada di Pulau Lombok. Koleksi sampel morfologi (daun,bunga, buah, dan biji) dilakukan dengan menggunakan metode jelajah (eksplorasi). Skoring dan standarisasi dilakukan pada 78 karakter morfologi. Karakter genetik diperoleh dengan menggunakan metode RAPD (Random Amplified Polymorphism DNA). Lima primer RAPD menghasilkan 63 fragmen DNA. Indeks similaritas dihitung menggunakan koefisien Jaccard dan konstruksi dendrogram menggunakan metode UPGMA (Unweighted Pair Group Method Using Arithmetic Mean). Analisis data dilakukan menggunakan software NTSYS ver.2.01. Hasil penelitian menunjukkan dari 26 sampel plasma nutfah kacang komak yang dikoleksi, berdasarkan karakter morfologis kacang komak menunjukkan variasi pada wama batang, karakteristik daun (wama tulang daun dan bentuk daun), karakteristik polong (wama polong, wama tepi polong, dan tekstur polong), karakteristik biji (bentuk dan wama biji, keberadaan bintik pada biji). Secara fenetik kacang komak dibagi menjadi 2 klaster besar dengan nilai similaritas antara 69-96%, LOTENG 9 dan LOTENG 14 mempunyai nilai similaritas tertinggi (96%) berdasarkan karakter morfologis. Berdasarkan karakter molekular plasma nutfah kacang komak terbagi menjadi 4 klaster dengan nilai similaritas antara 65-95%, LOTIM 2 dan LOTIM 3 memiliki nilai similaritas tertinggi (95%). Penggabungan karakter morfologis dan molekular membagi plasma nutfah kacang komak menjadi 3 klaster dengan nilai similaritas antara 71- 89%, LOTIM 4 dan LOTENG 5 memiliki nilai similaritas tertinggi (89%). Pola pengelompokan plasma nutfah kacang komak dengan penggabungan karakter morfologis dan molekular cenderung mirip dengan pengelompokan berdasarkan karakter morfologis.

Hyacinth bean (Lablab purpureus (L.) Sweet) is a member of Fabaceae which has high economic potential but is still treated as an underutilized crop. Research on hyacinth bean in Indonesia so far is only focused on bio-chemical content and protein isolate. However, the study on morphological and genetic variation of hyacinth bean in Indonesia particularly in Lombok, West Nusa Tenggara has never been conducted. The aims of this research were to study morphological and genetic variation and the phenetic relationship of hyacinth bean germplasm (Lablab purpureus (L.) Sweet) in Lombok, West Nusa Tenggara. The research was conducted in 4 regencies (East Lombok, Central Lombok, West Lombok and North Lombok) and samples (stem, leaf, flower, fruit, and seed) were collected using exploration method. Scoring and standarization were done on 78 morphological characters. Molecular characters were collected using RAPD (Random Amplified Polymorphism DNA). Five RAPD primers generated 63 total DNA fragments. Similarity index was calculated using Jaccard coefficient and UPGMA (Unweighted Pair Group Method Using Arithmetic Mean) was performed to construct dendrogram. Data analysis was performed by NTSYS software ver.2.01. The result showed that based on the morphological characters, the 26 collected samples showed that there were morphological differences on stem color, leaf morphology (vein colour and leaf shape), pod morphology (color, edge, texture), and seed morphology (color, shape, and spot existence). Furthermore, phenetic relationship of 26 OTU's (Operational Taxonomy Unit) were divided into 2 clusters with similarity coefficient ranging from 69-96%, LOTENG 9 and LOTENG 14 were the most closely similar (96%) based on morphological characters. Based on molecular characters hyacinth bean germplasms were divided into 4 clusters with similarity coefficient ranging from 65-95%, LOTIM 2 and LOTIM 3 were the most closely similar (95%). Combination of morphological and molecular characters divided hyacinth bean into 3 clusters with similarity coefficient ranging from 71-89%, LOTIM 4 and LOTENG 5 were the most closely similar (89%). Dendrogram's clustering pattern using combination of both characters similar to dendrogram's clustering pattern using morphological characters.

Kata Kunci : kacang komak (Lablab purpureus (L.) Sweet), variasi morfologis, variasi genetik, hubungan fenetik, Lombok