Identifikasi kromosom dalam penentuan jenis kelamin tanaman salak (Salacca zalacca (Gaertner) Vess)

HADI, Purwono Sulistyo, Dr.Ir. Aziz Purwantoro, M.Sc

2001 | Tesis | S2 Agronomi

Masalah utama yang sering menjadi kendala di lapangan adalah kesulitan penentuan jenis kelamin bibit salak pondoh dari biji secara dini. Ada dua mitos petani untuk menentukan jenis kelamin tersebut. 1. Berdasarkan jumlah biji. Biji ganjil menjadi jantan dan biji genap menjadi betina. 2. Berdasarkan perkecambahan biji. Biji " berkendhit '' menjadi betina dan biji tidak " berkendhit menjadi jantan. Untuk memecahkau persoalan ini telah dilakdcan penelitian dengan tujuan untuk mengetahui perbedaau kromosom antara tanaman salak pondoh betina, jantan dan salak bali (hermaprodit). Ujung akar bibit tanaman salak pondoh betina, jantan dan salak bali (hermaprodit) digunakan dalam penelitian ini. Metode squash (pemencetan) digunakan untuk mendapatkan preparat kromosom yang baik. Hasil penelitian menunjukkan bahwa tidak ada perbedaan jumlah kromosom antara betina , jantan dan hermaprodit, yaitu 2n = 28 sedangkan struktur kromosom antara betina, jantan dan hermaprodit berbeda. Betina mempunyai formula n = 1 1 m +2sm+ 1T; jantann=12m+ 1 sm+ IT dan hermaprodit n = 9 m + 3 s m + 2 T . Kromosom seks tidak ditemukan dalam bentuk yang heteromorphic pada pasangan kromosom homolog untuk menentukan jenis kelamin. Perbedaan ukuran panjang absolut terdapat pada beberapa kromosom. Biji " berkendhit " dan tidak " berkendhit " saat berkecambah dapat digunakan sebagai kriteria untuk penentuan jenis kelamin tanaman salak pondoh ( Salacca zalacca (Gaertner) Voss).

Sex determination on Salacca plant at early stage is the crucial problem. There are 2 farmer's consideration concerning to determine sex of these plant at early stage. First, based on the amount of the seed. Odd seed will become male and even seed will become female. Second, based on the seed germination. The seed which show the " belt " will become female and non " belt " seed will become male. For this problem solving, The research was conducted due to those consideration with purpose to determine the chromosomes differences between female, male and hermaphrodite. Root tips of the female,male and hermaphrodite plant was used in this study.. Chromosomes preparation was stained with fuchsin andthe squash method was applied on it. The result showed that there are no differences on the number of chromosomes among female, male and hermaphrodite plant, i.e. 2n = 28. On the other hand structure of the chromosomes was different between female, male and hermaphrodite formula. Female has n = 1 1 m + 2 sm + 1 T ; male n = 12 m + 2 sm + 1 T and hermaphrodite n = 9 m + 3 sm + 2 T. Sex chromosomes cannot be found on heteromorphic shapes on homolog chromosomes to determine sex. On the contrary, absolute length of the chromosomes showed differences between female, male and hermaphrodite. Seeds which show " belt " and non " belt " during their germination could be used as criteria for sex determination on Salacca zalacca (Gaertner) Voss in the early stage.

Kata Kunci : Tanaman Salak,Kromosom,Jenis Kelamin