<p>ABSTRAK<br />Tembakau bondowoso merupakan tembakau lokal rajangan yang<br />berkembang di Kabupaten Bondowoso, Jawa Timur. Saat ini ada delapan<br />kultivar dengan karakter produksi, mutu, dan ketahanannya terhadap<br />penyakit yang berbeda. Layu bakteri (Ralstonia solanacearum), busuk<br />batang berlubang (Pectobacterium carotovorum), dan lanas (Phytophthora<br />nicotianae) merupakan penyakit yang sering menyebabkan turunnya<br />produksi tembakau bondowoso. Evaluasi ketahanan delapan kultivar<br />tembakau bondowoso (Samporis, Serumpung, Marakot, Samporis Lokal,<br />Samporis AH, Samporis CH, Samporis B. Disbun, dan Deli) terhadap<br />ketiga patogen tersebut dilaksanakan di laboratorium dan rumah kasa Balai<br />Penelitian Tanaman Pemanis dan Serat (Balittas) mulai bulan April sampai<br />dengan Oktober 2011. Penelitian terhadap ketiga patogen tersebut<br />dilakukan secara terpisah. Masing-masing kultivar ditanam sebanyak 10<br />tanaman, 1 tanaman/polibag. Setiap perlakuan (kultivar) diulang 3 kali dan<br />disusun dalam rancangan acak kelompok (RAK). Inokulasi R.<br />solanacearum dan P. carotovorum dilakukan secara terpisah 24 jam<br />sebelum transplanting. Inokulasi P. nicotianae dilakukan dengan dua cara,<br />yaitu melalui akar dan pangkal batang. Inokulasi akar sama dengan cara<br />inokulasi bakteri. Inokulasi pangkal batang dilakukan pada tanaman<br />berumur 2 minggu setelah transplanting. Pengamatan intensitas penyakit<br />dilakukan setiap minggu selama 11 minggu. Hasil penelitian menunjukkan<br />bahwa kultivar Samporis CH, Samporis, dan Deli tahan terhadap P.<br />carotovorum, R. solanacearum, dan P. nicotianae. Kultivar Samporis CH.,<br />Samporis, dan Deli ketahanannya lebih tinggi terhadap ketiga patogen,<br />dengan intensitas penyakit berkisar antara 3,3%-6,7%. Kultivar Marakot<br />sangat rentan terhadap ketiga patogen tersebut dengan tingkat keparahan ≥<br />50%. Demikian pula kultivar Samporis AH yang rentan terhadap R.<br />solanacearum, P. nicotianae dan P. carotovorum dengan intensitas<br />penyakit 23,3-53,3%. Oleh karena itu, kultivar Samporis CH, Samporis,<br />dan Deli cocok dikembangkan pada lahan endemik penyakit tular tanah di<br />Kabupaten Bondowoso.<br />Kata kunci: tembakau bondowoso, Pectobacterium carotovorum<br />Phytophthora nicotianae, Ralstonia solanacearum,<br />ketahanan</p><p>ABSTRACT<br />Bondowoso tobacco is a local type of sliced tobacco which is<br />restrictedly cultivated in Bondowoso Regency, East Java. There are eight<br />cultivars known, ie. Samporis, Serumpung, Marakot, Samporis Lokal,<br />Samporis AH, Samporis CH, Samporis B. Disbun, and Deli with their own<br />distinctive characters on their production, quality, and resistance to<br />diseases. Bacterial wilt (Ralstonia solanacearum), hollow stalk rot<br />(Pectobacterium carotovorum), and blackshank (Phytophthora nicotianae<br />are the main cause of bondowoso tobacco production loss. Evaluation on<br />the resistance level of the cultivars to the three pathogens above has been<br />conducted at a laboratory and screen house scale in Indonesian Sweetener<br />and Fibre Crops Research Institute from April to October 2011. The<br />evaluation of each pathogen was conducted separately. Each evaluation of<br />the pathogen per cultivar used 10 plants planted individually in a polybag.<br />The experiment was arranged in a randomized block design with 3<br />replicates. R. solanacearum and P. carotovorum were separately<br />inoculated on the test plants 24 h before transplanting. The inoculation of<br />P. nicotianae was done twice via the root and stem. Disease intensity was<br />observed weekly for 11 weeks. The results showed that Samporis CH,<br />Samporis, and Deli cultivars were resistant to P. carotovorum, R.<br />solanacearum and P. nicotianae, whereas Samporis and Deli cultivars<br />were more resistant to the pathogens (disease intensity ranged 3.3-6.7%).<br />Marakot cultivar was very susceptible to all of the three pathogens (disease<br />intensity ≥ 50%). Similarly, Samporis AH cultivar was also susceptible to<br />the pathogens with disease intensity ranged 23.3-53.3%. The study<br />indicated that Samporis CH, Samporis, and Deli cultivars are suitable to be<br />cultivated in the endemic soil born pathogen areas of Bondowoso<br />Regency.<br />Key words: bondowoso tobacco, Pectobacterium carotovorum,<br />Phytophthora nicotianae, Ralstonia solanacearum,<br />resistance</p>