Genetic Diversity Analysis of Jatropha Curcas Provenances
Using Randomly Amplified Polymorphic DNA Markers
Dani Satyawan* and I Made Tasma
Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development, Jl. Tentara Pelajar 3A, Bogor 16111
Phone (62-251) 8337975; Facs. (62-251) 8338820; *E-mail: d.satyawan@gmail.com
Submitted: 22 Oktober 2010; Accepted: 9 Maret 2011
ABSTRAK
Analisis Keragaman Genetik Jarak Pagar (Jatropha
Curcas) Menggunakan Marka RAPD. Dani Satyawan dan
I Made Tasma. Jarak pagar (Jatropha curcas L.) adalah
tanaman non pangan yang bijinya dapat menghasilkan
minyak untuk digunakan dalam produksi biodiesel atau
langsung dipakai sebagai bahan bakar bagi mesin diesel
yang telah dimodifikasi. Tujuan penelitian ini adalah untuk
mengetahui keragaman genetik koleksi tanaman jarak pagar
Badan Penelitian dan Pengembangan Pertanian yang di-
tanam di Kebun Percobaan Pakuwon (Sukabumi, Jawa
Barat) dengan menggunakan marka RAPD. Sebanyak 50
aksesi jarak pagar dan satu aksesi Jatopha integerrima
dianalisis keragaman genetiknya menggunakan 14 primer
RAPD dengan kandungan G+C antara 60-80%. Dari 14
primer tersebut diperoleh 64 pita DNA dengan tingkat poli-
morfisme sebanyak 95,7%. Beberapa pita DNA yang dihasil-
kan tidak konsisten dan reproducible sehingga dilakukan
reaksi ulangan untuk setiap primer yang digunakan demi
meminimalisir kesalahan skor marka. Data pita DNA yang
dihasilkan selanjutnya digunakan untuk analisis keragaman
genetik dengan menggunakan Unweighted Pair Group
Method Arithmetic (UPGMA) dan koefisien Dice, dan hasil
yang didapat menunjukkan bahwa aksesi yang dianalisis
memiliki koefisien kesamaan antara 0,2 dan 0,98, dengan
rerata sebesar 0,75. Analisis dendrogram membagi aksesi-
aksesi ke dalam dua kelompok besar, dengan satu outlier
dari Lampung Selatan. Pembagian kelompok tidak berko-
relasi dengan daerah asal masing-masing aksesi, sehingga
konsisten dengan hipotesis bahwa tanaman jarak pagar ba-
ru masuk ke Indonesia sekitar 4 abad lalu dan penyebaran-
nya lebih banyak difasilitasi oleh manusia. Tingginya rerata
koefisien kesamaan menunjukkan bahwa keragaman ge-
netik koleksi ini cukup rendah, sehingga di masa depan di-
perlukan penambahan aksesi dengan latar belakang genetik
yang bervariasi untuk semakin meningkatkan produktivitas
tanaman hasil pemuliaan jarak pagar.
Kata kunci: Jatropha curcas, marka RAPD, keragaman
genetik.
ABSTRACT
Genetic Diversity Analysis of Jatropha Curcas
Provenances Using Randomly Amplified Polymorphic
DNA Markers. Dani Satyawan and I Made Tasma.
Jatropha curcas nuts are rich in oil that is higly suitable for
Hak Cipta © 2011, BB-Biogen
the production of bio-diesel or to be used directly in
modified diesel engines. The objective of this study was to
assess the extent of genetic diversity among 50 J. curcas
provenances and one accession of J. integerrima using
RAPD markers. The fifty J. curcas provenances were
collected from ecologically diverse regions of Indonesia, and
planted in the Pakuwon Experimental Station (Sukabumi,
West Java). Fourteen RAPD primers with 60-80% G+C
content were used in this genetic diversity analysis and
produced 64 bands with 95.7% polymorphism level. The
Polymerase Chain Reactions used to generate the RAPD
bands sometimes produced inconsistent and non-
reproducible results, necessitating the duplication of each
reaction to prevent scoring errors. Sixty one validated bands
were subsequently used for genetic diversity analysis using
Unweighted Pair Group Method Arithmetic (UPGMA)
method and Dice coefficients. It was shown that the
similarity coefficients among the provenances ranged from
0.2 to 0.98 with an average similarity of 0.75. Dendrogram
analysis produced two major groups of provenances, with
one outlier from South Lampung. There was no tendency for
provenances originated from nearby regions to cluster
together in each group, and several provenances showed
more similarities with provenances originated from distant
regions. This pattern lent credence to reports that Jatropha
was introduced to Indonesia around four centuries ago and
was mainly spread by humans. Based on the mean
similarities among the accessions and their clustering
pattern, the genetic diversity of the Jatropha collection
appeared to be fairly low. Future additions of genetic
materials from more diverse genetic background will be
necessary to maintain the current progress of Jatropha
improvement program.
Keywords: Genetic diversity, RAPD markers, Jatropha
curcas.
INTRODUCTION
Indonesian population and economic
developments have increased each year, resulting in a
similar increase in national consumption for fossil-
based fuels even when the national fuel production is
lower than the national demands. As a consequence,
the country position has shifted from a net exporter to
become a net importer. The world fuel price has also
shown extreme volatility, at one time even sky-
rocketing close to US$ 150 per barrel, making the
Jurnal AgroBiogen 7(1):47-55