ABSTRAK. Perakitan kultivar yang tahan terhadap penyakit busuk lunak yang disebabkan Erwinia carotovora dapat dilakukan dengan teknik induksi mutasi. Tujuan penelitian ialah mengetahui pengaruh mutagen etil metan sulfonat (EMS) terhadap perubahan genetik di antaranya kapasitas regenerasi tanaman anggrek Phalaenopsis pada kultur in vitro dan mengetahui lethal concentration (LC) mutagen EMS pada anggrek hibrida Phalaenopsis. Percobaan ditata dalam rancangan acak lengkap dengan sembilan perlakuan konsentrasi EMS dan diulang tiga kali. Mutagen kimia yang digunakan yaitu EMS dengan konsentrasi 0 ; 0,025 ; 0,050 ; 0,075 ; 0,1; 0,125 ; 0,15 ; 0,175; dan 0,2%. Eksplan berupa meristem aksilar anggrek hibrida Phalaenopsis ditanam pada medium dasar MS+ 2 ml/l BA + 1 ml/l NAA dan diinkubasi pada ruang kultur. Hasil penelitian menunjukkan bahwa etil metan sulfonat memberi pengaruh pada pertumbuhan meristem hibrida Phalaenopsis dalam membentuk tunas. EMS dengan konsentrasi 0,025 dan 0,05% memberi pengaruh yang lebih baik terhadap jumlah tunas dan tinggi tunas. LC 50 untuk karakter persentase pembentukan tunas ialah 0,112%. Terdapat dua konsentrasi EMS, yaitu 0,025 dan 0,05% yang memberi pengaruh terbaik pada pembentukan tunas hibrida Phalaenopsis. Diperoleh beberapa regeneran mutan potensial dari berbagai perlakukan < 0,15% EMS yang perlu diuji dengan isolat Erwinia carotovora.Katakunci: Hibrida anggrek Phalaenopsis; Induksi mutasi; EMS ABSTRACT. Qosim, WA, Istifadah, N, Djatnika, I, and Yunitasari 2012. Effect of Ethyl Methane Sulphonate Mutagent to Capacity of Shoot Regenerations on In Vitro PhalaenopsisHybrid. To improve cultivars resistance to soft rot disease caused by Erwinia carotovora can be done by using mutation induction. The research objective was to determine the effect of EMS mutagent Phalaenopsis hybrid to change the genetic i.e. capacity of plant regeneration in vitro culture and the lethal concentration (LC) of EMS mutagent in Phalaenopsis hybrid. The experiment was arranged in a completely randomized design with nine concentrations of EMS treatment and repeated three times. The mutagent of EMS concentrations used were 0, 0.025; 0.050; 0.075; 0.1; 0.125; 0.15; 0.175; and 0.2%. The meristem axilar as explant was be grown on basic medium MS suplemented with 2 ml/l BA + 1 ml/l NAA and incubated in culture room. The results showed that the influence on growth of EMS meristem Phalaenopsis hybrids. The EMS mutagent with concentration of 0.025 and 0.05% gave better effect to the high number of shoots and buds. LC 50 of the percentage of bud formation character was 0.112%. Two EMS concentrations were 0.025 and 0.05% provided the best influence on the formation of shoot Phalaenopsis hybrid. There were many regenerants potential mutant from several EMS treatments < 0.15 % that should be tested by isolate of E. carotovora.

Citrus hystrixis a famous horticutural crops product today. Fresh fruits of Citrus hystrix from Indonesia are mainly exported to European countries by PT Nusantara Segar Global under the trademark of Java Fresh. Futhermore, the seedlings of Citrus hystrix were also used to be a rootstock for RGL citrus due to its vigorous root growth, adataptive to marginal land, and resistance to dry season. The objective of research was to determine the effects of difference kind and concentration of cytokinin to induce shoot of Citrus hystrix. The research was conducted from January to April 2019 at the Laboratory of Biotechnology and Tissue Culture, Faculty of Agriculture, Bengkulu University. The research was designed to be Completely Randomized Block Design (CRBD). First factor was kind of cytokinin (BAP and Kinetin). Second factor was the concentration of cytokinins (0 ppm, 1 ppm, 2 ppm, 3 ppm, 4 ppm, and 5 ppm). Therefore, there were 12 combinations with 3 replications. The results show, the number of shoot leaf of Citrus hystrix shows a different respon to the type of cytokinin. The best type of cytokinin in the shoot of Citrus hystrix was BAP, that produced the highest number of leaves, the highest number of shoots and the heaviest wet weight of shoots, namely 10.42 leaves/bottle, 3.2 shoots and 0.46 gr. The optimum concentration of BAP was 2.58 ppm.