Uji Efikasi Teknik Kultur Meristem dan Kemoterapi untuk Eliminasi Sugarcane Streak Mosaic Virus (SCSMV) pada Tebu

Penggunaan benih bebas virus merupakan salah satu cara pengendalian penyakit virus. Jaringan tanaman dapat dibebaskan dari virus melalui aplikasi teknik eliminasi virus, seperti termoterapi, kemoterapi, kultur meristem, dan krioterapi. Tujuan penelitian ini adalah untuk menguji respon varietas tebu terhadap perlakuan teknik kultur meristem dan kemoterapi dengan bahan antiviral, serta untuk mengetahui efektivitasnya dalam mengeliminasi virus sugarcane streak mosaic virus (SCSMV) pada tebu. Penelitian ini dilakukan pada April−November 2015 di Laboratorium Kultur Jaringan, Balai Besar Penelitian dan Pengembangan Bioteknologi dan Sumberdaya Genetik Pertanian dan Laboratorium Virologi, Fakultas Pertanian, Universitas Gadjah Mada. Penelitian terdiri atas tiga tahap, yaitu 1) Deteksi virus dari tanaman induk, 2) Aplikasi teknik kultur meristem dan kemoterapi, serta 3) Indeksing virus. Bahan tanaman yang digunakan adalah sebelas varietas tebu (GMP3, PS865, dan Kentung asal Bogor, PS862 dan Cening asal Cirebon, PS881 asal Jember, PSJK922 asal Malang, serta PS864, PS881, PSJK922, PSJT941 asal Pati). Deteksi virus dilakukan secara RT-PCR dengan primer universal MJ dan primer spesifik SCSMV. Bahan antiviral yang digunakan untuk kemoterapi adalah Ribavirin (0 dan 25 µg/l). Hasil uji RT-PCR menggunakan primer universal MJ menunjukkan bahwa empat varietas (GMP3 asal Bogor, PS864 dan PSJT941 asal Pati, serta Cening asal Cirebon) terinfeksi oleh Potyvirus . Empat varietas lainnya (PS862 asal Cirebon, PS881 asal Jember, PSJK922 asal Malang, dan Kentung asal Bogor) terbukti terserang virus SCSMV berdasarkan uji RT-PCR dengan primer spesifik. Seluruh meristem mampu beregenerasi membentuk tunas. Penggunaan Ribavirin 25 µg/l tidak menyebabkan penurunan daya tumbuh meristem (50−100%), bahkan seluruh varietas mampu bermultiplikasi tunasnya dibandingkan dengan kontrol yang hanya memiliki daya tumbuh 0−100%, dan tidak semua varietas mampu bermultiplikasi tunasnya. Secara tunggal, aplikasi teknik kultur meristem tidak mampu mengeliminasi virus SCSMV, namun jika dikombinasikan dengan perlakuan kemoterapi maka virus SCSMV dapat tereliminasi dengan efikasi sebesar 44,4%. The use of virus-free seedling is an option for controlling viral disease that can be obtained through the application of viral elimination method. Plant tissues can be eliminated from virus infection by applying virus thermotherapy, chemotherapy, meristem culture, and cryotherapy. The research objectives were to examine the response of sugarcane varieties to meristem culture treatments and antiviral agent and also to determine the efficacy rate of both techniques in eliminating SCSMV disease. The study was conducted atTissuseCulture Laboratory, Indonesian Center for Agricultural Biotechnology and Genetic Resources Research andDevelpoment, and also at Virology Laboratory, Faculty of Agriculture, Gadjah Mada University. This study consisted of three activities: 1) Virus detection of the mother plants, 2) Application of meristem culture and chemotherapy, and 3) Virus indexing. The plant material used was eleven varieties of sugarcane (GMP3, PS865, and Kentung from Bogor, PS862 and Cening from Cirebon, PS881 from Jember, Malang PSJK922 origin, as well as the PS864, PS881, PSJK922, PSJT941 from Pati). Virus detection was performed by RT-PCR assay with universal primer of MJ and specific primers of SCSMV. Antiviral used for chemotherapy was Ribavirin (0 and 25 µg/l). The result of RT-PCR using universal primers MJ showed that four varieties (GMP3 from Bogor, PS864 and PSJT941 from Pati, and Cening from Cirebon) were infected by Potyvirus. Based on RT-PCR assay with specific primer, four other varieties (PS862 from Cirebon, PS881 from Jember, PSJK922 from Malang, and Kentung from Bogor) were infected by SCSMV. All of meristems were able to regenerate to form shoots. The use of Ribavirin (25µg/l) did not decrease the growth rate of meristems and the shoots of all of the varieties could be multipied compared to control where the shoots could not be multiplied in all varietis. The application of meristem culture technique was not able to eliminate the SCSMV, but when it was combined with chemotherapy treatment, the SCSMV virus could be eliminated with the efficacy rate of 44.4%.