Genetic Variability of 11 Local Cacao Clones Derived from West Sumatra Using SSR Markers

Abstract

ABSTRAKIndonesia is the third largest cacao producing-country in the world and known having many superior local clones, such as that found in Lima Puluh Kota Regency, West Sumatra. However, there is lack of information about genetic background of those local cacao clones. This study aimed to assess genetic variability of 11 local cacao clones collected from Lima Puluh Kota Regency, West Sumatra using SSR markers. The research was conducted in the Integrated Laboratory, Indonesian Industrial and Beverage Crops Research Institute (IIBCRI), Sukabumi, from August to November 2016. The genetic variabilities of local cacao studied were compared with 9 national varieties as reference genomes. Total genomic DNA of the plants was isolated using CTAB method. Cacao DNA was amplified using 18 SSR markers to determine their genetic variability. Afterward, the amplified DNA was separated using 6% non-denaturing polyacrylamide gel electrophoresis. The result exhibited that 12 markers were polymorphic. Further analysis of these polymorphic markers using PowerMarker program revealed a total of 83 alleles were obtained from all cacao clones analyzed. Meanwhile, PIC values ranged from 0.55 to 0.86 with an average of 0.70. A genetic similarity matrix based on UPGMA revealed three main groups at 68% similarity coefficients. Interestingly, all of the 11 local cacao clones were clearly distinguished each other and also from the national varieties. The result demonstrated the usefulness of SSR markers for discriminating local cacao clones.Further study is required to use these local clones in cacao breeding programs.Keywords: Genetic variability, local clones, SSR markers, Theobroma cacao L. ABSTRACT Indonesia adalah negara produsen kakao terbesar ketiga di dunia yang memiliki banyak genotipe kakao unggul lokal, seperti yang terdapat di Kabupaten Lima Puluh Kota, Sumatera Barat. Namun demikian, hanya sedikit informasi tentang latar belakang genetik dari kakao lokal tersebut yang diketahui. Tujuan penelitian adalah untuk menilai keragaman genetik 11 klon kakao lokal yang dikoleksi dari Kabupaten Lima Puluh Kota, Sumatera Barat menggunakan marka SSR. Penelitian dilaksanakan di Laboratorium Terpadu Balai Penelitian Tanaman Industri dan

Keragaman Genetik Klon Kakao Lokal Sulawesi Tenggara Berdasarkan Marka SSR dan Karakter Morfologi

“…Hasil penelitian sebelumnya telah membuktikan keefektifan 14 marka SSR polimorfik dalam mengelompokkan kakao hasil eksplorasi di daerah Kolaka, Sulawesi Tenggara menjadi 3 kelompok berbeda pada nilai kesamaan genetik 36% (Rubiyo et al, 2015). Demikian juga hasil penelitian Tresniawati, Izzah, Sulistiyorini, & Wicaksono (2017) yang berhasil mengelompokkan 11 klon kakao lokal hasil eksplorasi di Kabupaten Lima Puluh Kota, Sumatera Barat berdasarkan 12 marka SSR polimorfik pada nilai kesamaan genetik 68%. Karakterisasi secara molekuler sebaiknya juga digunakan dalam mengidentifikasi tanaman untuk mendukung hasil karakterisasi secara morfologi.…”