<![CDATA[Javanese cardamom plants are mostly propagated vegetatively using its rhizome. Therefore, the genetic variability is quite low so that the variability needs to be enhanced, one of them is by gamma irradiation. The objectives were to reveal the optimal dose (LD20 and LD50) of gamma irradiation on Java cardamom seedlings and to assess the performance of seedlings post irradiation. The experiment was arranged in randomized complete block design with 6 replications. Gamma ray used were 0, 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275 and 300 Gy. Survival rate, quantitative and qualitative observation of plant growth were conducted. Irradiation was conducted on mature plant. Result showed the LD20 and LD50 values were 55,89 Gy and 100,75 Gy. Seedling showed necrosis on leaves and stem area after irradiation especially in high gamma ray doses. Until 25 weeks after irradiation, plants irradiated with 50 Gy and 100 Gy produced 16.7% new shoots, but their development was very slow. Control plants produced 5.2 new shoots with good agronomic appearance and 67% produced flowers at 25 weeks after irradiation. Furthermore, the irradiation dose for cardamom cultivation needs to be optimized in the range of 50-100 Gy by using younger plant material. ABSTRAK Tanaman kapulaga jawa sebagian besar diperbanyak secara vegetatif dengan menggunakan rimpangnya. Oleh karena itu, variabilitas genetiknya cukup rendah sehingga variabilitas tersebut perlu ditingkatkan, salah satunya dengan iradiasi sinar gamma. Penelitian ini bertujuan untuk mengetahui dosis optimal (LD20 dan LD50) iradiasi gamma pada bibit kapulaga Jawa dan menilai keragaan bibit kapulaga pasca iradiasi gamma. Percobaan menggunakan rancangan kelompok lengkap teracak dengan 6 ulangan. Iradiasi sinar gamma digunakan adalah 0, 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275 dan 300 Gy. Tingkat kelangsungan hidup, pengamatan kuantitatif dan kualitatif pertumbuhan tanaman dilakukan. Iradiasi dilakukan pada tanaman dewasa. Hasil menunjukkan nilai LD20 dan LD50 sebesar 55,89 Gy dan 100,75 Gy. Bibit menunjukkan nekrosis pada area daun dan batang setelah penyinaran terutama pada dosis sinar gamma tinggi. Sampai umur 25 minggu setelah iradiasi (MSI), tanaman yang diiradiasi 50 Gy dan 100 Gy menghasilkan 16,7% tunas baru, namun perkembangannya sangat lambat. Tanaman kontrol menghasilkan 5,2 tunas baru dengan penampilan agronomis baik dan 67% menghasilkan bunga pada umur 25 minggu setelah iradiasi. Selanjutnya dosis iradiasi pada budidaya kapulaga perlu dioptimalkan pada kisaran 50-100 Gy dengan menggunakan bahan tanaman yang lebih muda.]]>
