<p>ABSTRAK</p><p>Nematoda puru akar (Meloidogyne sp.) merupakan penyakit yangtergolong penting dan banyak menyerang pertanaman kenaf di lahanpengembangan maupun pembenihan, sehingga banyak menimbulkankerugian bagi petani karena terjadi penurunan produktivitasnya. Tanamankenaf (H. cannabinus) umumnya tidak tahan nematoda, namun kerabatdekat kenaf dari jenis liar seperti H. radiatus (radiatus) diketahuimengandung gen ketahanan terhadap nematoda. Persilangan inter spesifikantara kenaf dan radiatus yang beda spesies, diharapkan akan dapatmentransfer gen ketahanan dari radiatus ke kenaf, sehingga diperolehvarietas unggul kenaf yang tahan nematoda. Tujuan penelitian ini adalahuntuk mengetahui variabilitas genetik sifat ketahanan tanaman kenafterhadap serangan M. incognita pada F1 dibandingkan dengan keduatetuanya. Kegiatan persilangan interspesifik antara kenaf (H. cannabinus)dan radiatus (H. radiatus) dilakukan di KP. Karangploso Malang padaTahun 2002, sedangkan uji ketahanan nematoda puru akar (M. incognita)terhadap keturunan dan kedua tetuanya dilaksanakan di Desa Kendalrejo,Kabupaten Blitar pada bulan Februari s/d Agustus 2003. Pengujianketahanan di lapang dilakukan menggunakan metode baris tanpa ulanganpada jarak tanam 20 x 20 cm, dengan perlakuan terdiri dari lima set hasilpersilangan dan kedua tetuanya yakni 20 populasi F1, 20 populasi P1 dan20 populasi P2, dengan masing-masing populasi 20 tanaman. Hasil ujitanah di laboratorium menunjukkan bahwa rata-rata kandungan larva M.incognita (sebagai populasi awal) adalah sebesar 96 ekor/100 ml tanahdan dikategorikan sangat tinggi. Sedangkan hasil identifikasi sidik pantat(berdasarkan perenial patternnya) terhadap larva betina dewasa diketahuibahwa jenis nematoda di lokasi penelitian adalah dari spesies Meloidogyneincognita. Pengamatan dan perhitungan larva M. incognita dilakukan diLaboratarium Hama dan Penyakit Balittas, Malang. Pengamatan dilakukanterhadap jumlah puru akar per tanaman, kerusakan akar tanaman, danpopulasi larva M. incognita dalam tanah sebagai faktor R (R = reproduksilarva). Untuk menggolong-golongkan tingkat ketahanan terhadap M.incognita digunakan metode Zeck melalui indeks kerusakan akar. Darihasil penelitian menunjukkan bahwa, semua keturunan F1 dari 5persilangan interspesifik antara KR 6 x Kal II, KR 11 x Kal II, KR 12 xKal II, Hc G-1 x Kal II, dan Hc G-51 x Kal II tidak ada yang tahanterhadap serangan M. incognita. Nilai ketahanan genotipe F1 terletak diantara tetua jantan (Kal II/ radiatus) yang tahan dan tetua betina (kenaf)yang sangat rentan.</p><p>Kata kunci : Hibiscus cannabinus L., interspesifik, variabilitas genetik,ketahanan, Meloidogyne incognita</p><p>ABSTRACT</p><p>Resistance variability of kenaf (Hibiscus cannabinus L.)genotypes to root-knot nematode (Meloidogyne incognitaL.)Root Knot Nematode (Meloidogyne incognita) is an importantdisease on kenaf plantation in the development area and its nursery. Thiscondition generates reduce of productivity and loss of farmers’ income.Kenaf plants are generally not resistant to nematode infestation, so theyneed resistant gene from other species (H. radiatus) to be transfered to H.cannabinus by interspecific hybridization. The objective of this researchwas to obtain genetic variability of kenaf resistance to Meloidogyneincognita attact. Interspecific hybridization between H. cannabinus and H.radiatus was conducted at KP Karangploso, Malang in 2002. Meanwhile,evaluation of F1 lines and their parents to M. incognita resistance wasconducted at Kendalrejo, Blitar on February to August 2003. In this area,the type of soil is medium fertile-light-sandy soil containing high densitiesof root-knot nematode larvae. Five sets of F1 resulted from hybridizationbetween H. canabinus and H. radiatus and their parents were planted in arow method without replication. Subsequently, these seeds were used asthe materials in this study. The observation and evaluation of these larvaewas performed at the Phytopathology Laboratory of the IndonesianTobacco and Fiber Crops Research Institute, Malang. The preliminaryresult showed that the average of the initial population was 96 larvae per100 ml of soil, which is categorized as a very high larvae content.Furthermore, the identification to the adult female larvae (perennial patternmethod) showed that the root-knot nematode found in the location ischaracterized as M. incognita. Parameters observed were total number ofgall per plant, degree of root damage, and populations of M. incognitalarvae in the soil as a R-factor (R = larvae reproduction). The degree ofresistance to M. incognita are analyzed according to Zeck method usingroot damage index. Results of this research are : all F1 from fiveinterspesific hybridization between KR 6 x Kal II, KR 11 x Kal II, KR 12x Kal II, Hc G-1 x Kal II, and Hc G-51 x Kal II are still more sucseptiblecompared to their male parent (Kal II) which is resistant to root-knotnematode.</p><p>Key words : Hibiscus cannabinus L., interspecific, genetic variability,resistance, Meloidogyne incognita</p>

<p>ABSTRAK</p><p>Serangkaian penelitian yang bertujuan untuk memperoleh galur-galur kenaf yang mampu beradaptasi dan menghasilkan serat yang tinggidi lahan Podsolik Merah Kuning (PMK) telah dilaksanakan mulai tahun2003 sampai dengan 2005. Sebanyak 13 galur kenaf dan 2 varietaspembanding diuji dalam rancangan acak kelompok dengan 3 ulangan yangdilaksanakan di 4 lokasi di Propinsi Kalimantan Timur, yaitu di Lempake(Kota Samarinda), Samboja (Kab. Kutai Kartanegara), Makroman (KotaSamarinda), dan Empas (Kab. Kutai Barat). Pemeliharaan dilakukan sesuaistandar pada masing-masing lokasi. Hasil penelitian menunjukkan bahwadari 13 galur kenaf yang diuji diperoleh 2 galur yang memiliki daya hasilserat tinggi dan beradaptasi luas di lahan PMK, yaitu galur 85-9-66-2 dan85-9-66-1 BB. Kedua galur tersebut mampu menghasilkan serat keringlebih tinggi dibanding varietas pembanding (KR 4 dan KR 11). Galur 85-9-66-2 memiliki rata-rata hasil serat 1,48 t/ha (meningkat 29,17% terhadapKR 4 dan 20,11% terhadap KR 11); dan galur 85-9-66-1 BB memilikirata-rata hasil serat 1,405 t/ha (meningkat 26,62% terhadap KR 4 dan17,73% terhadap KR 11).</p><p>Kata kunci : Hibiscus cannabinus L., stabilitas, adaptasi, podsolik merahkuning</p><p>ABSTRACT</p><p>Stability and adaptation of kenaf lines in yellow red podsolic soilA series of research to obtain some kenaf lines adaptable and highin fiber yield was conducted on yellow red podsolic soil from 2003 to2005. The 13 kenaf lines and 2 check varieties were tested in fourlocations of East Kalimantan Province, i.e. Lempake (Samarinda District),Samboja (Kutai Kartanegara District), Makroman (Samarinda District),and Empas (Kutai Barat District). The field experiment was arranged inrandomized complete block design with three replications. The resultsshowed that there were 2 kenaf lines that are high in fiber yield and widelyadapted on red yellow podsolic area, i.e. line 85-9-66-2 and 85-9-66-1 BB.Both lines are capable to produce higher fiber yield compared to checkvarieties (KR 4 and KR 11). The line 85-9-66-2 has average of fiber yield1.48 t/ha (increases 29,17% to KR 4 and 20,11% to KR 11); and line 85-9-66-1 BB has average of fiber yield 1,405 t/ha (increases 26,62% to KR4 and 17,73% to KR 11).</p><p>Key words : Hibiscus cannabinus L., stability, adaptation, yellow redpodsolic</p>

<p><strong>Promising kenaf lines adaptive to flooded area in Lanongan district</strong></p><p>The objective of the trial was lo ind out the most adaptive kenaf lines for flooded area in Lanongan district with a productivity of at least 20% higher than the best control varieties. The trial was conducted at Mojoasem viliage, Larcn sub-district, Lanongan. The trial was designed as a randomized block in 3 replications. Twenty kenaf genotypes consisting of 17 kenaf new lines and 3 control varieties were tested in this experiment. Plot size and plant spacing used was 2 m x 10 m and 20 cm x 15 cm, respectively. The seeds were sown in September 1999. Parameters observed were plant height, stem diameter, frish weight and dry ibre weight. The results showed that lines He 85-9-73 , He 85-9-75. and He 583 were the most promising lines for flooded areas Lanongan with the productivity of 3.4, 3.1, and 3.0 tons dry ibre per ha.</p>