Pathogenicity and Detection of Phytohormone (Gibberellic Acid and Indole Acetic Acid) Produced by Fusarium spp. that Causes Twisted Disease in Shallot

The twisted disease is one of the essential diseases in shallots caused by Fusarium spp. This study aimed to study pathogenicity and identify Fusarium species isolated from shallot plants with twisted symptoms in Nganjuk and Bantul areas. The Fusarium isolates were identified and then tested for pathogenicity levels and the effect of the hormones GA3 and IAA on shallot symptoms. Molecular identification using NF2 and NF4 successfully identified one isolate of Fusarium oxysporum, three isolates of F. acutatum, and three isolates of F. solani. Each of these species produces different symptoms. Pathogenicity test showed that all isolates had disease incidence reaching 100%, except isolates of F. solani1 causing wilt and F. solani3 causing twisted have the lower disease incidence were 77.8% and 77.7%, respectively. The investigation caused twisted shallot related to different symptoms was tested using the Thin Layer Chromatography (TLC) method. The result indicates that all isolates did not find IAA hormone. In contrast, the hormone GA3 was found in F. solani2 and F. solani3 isolates, caused bulb rot and twisted disease, respectively. Detection of IAA, GA3, and other hormones in shallot plants showed different symptoms should be studied further

Perkembangan bakteri pasteuria penrtrans pada nematoda puru akar (Meloidogyne spp).=Development of bacterium pasteuriia penetrans in root-knot nematodes ((Meloidogyne spp)

ABSTRAK Bacterium Pasteuria penetrans constitute one of a potential biological control agents against root-knot nematodes offer a great promise in the future. Development of P. penetrans spore in nematode was similar to fungal vegetative growth. At present, P. Penetrans is always mass cultured in its host {Meloidogyne spp.). The objective of this research were to study the life cycle of the bacterium in root-knot nematode, and to characterize morphology of spore of P. penetrans. Experimental results showed that : 1) spore of P. penetrans produced a germination tube which then penetrated the nematode body at 10 days after inoculation, 2) microcolonies were observed at 15 days after inoculation, 3) at 18 days after inoculation, vegetative hyphe became branched, segmented, and enlerged in some regions, 4) Sporogenic hypha was swollen, branched, and the tips were broken up at 23 days after inoculation, 5) spores were scattered all over nematode body at 28 days after inoculation, and 6) single endospore was ready to penetrate host body at 30 days after inoculation. Keywords: bacterium P. penetrans â root-knot nematod

Banana Bunchy Top Virus Molecular Confirmation and DNA-S Phylogenetic of some Banana Isolates from Indonesia

This study was aimed to confirms the Banana Bunchy Top Virus (BBTV) infection of ten banana accessions from Indonesia through PCR assay using primer of BBTV coat protein (CP) gene, also the sequences characteristics and phylogeny. Preliminary morphological results showed five acessions were positively infected with slight to severe intensity symptoms i.e. Pisang Berlin, Candi, Billa, Morosebo, and Mas Kripik; and five accessions were symptomless i.e. M. acuminata var. rutilifes and M. balbisiana, Pisang Ebung, Madu and Moseng. However, PCR results qualitatively confirms that all accessions were positively infected. Two sizes of amplicons were identified. Pisang Candi isolate was showing ±500 bp amplicons, whereas the others were ±1000-1100 bp. The total aligned and selected BBTV CP sequences of 36 accessions (bananas and other host species) was 450 nt. It was considered highly conserved (85.55%), low G+C content (41%), and high genetic similarities (92.47 to 100%). Phylogenetic analysis delineates isolates into two large groups, i.e. the Asian group (East Asia and South-east Asia) and the South Pacific group (South Asia, Africa and the Pacific). The findings of this study are usefull for broader applicability of further banana breeding program particularly for mitigation, selection and evaluation of banana with BBTV resistance

Potensi Erionota Thrax Sebagai Agen Penyebar Patogen Penyebab Penyakit Layu Bakteri Pada Tanaman Pisang (Blood Disease Bacterium)

Potential of Erionota thrax to spread the causal agen of banana bacterial wilt (Blood Disease Bacterium). This study was conducted in Gerbosari, Samigaluh, Kulonprogo, Yogyakarta and in the Laboratory of Bacteriology and Entomology, Faculty of Agriculture, Gadjah Mada University, Yogyakarta during December 2002 to June 2003. The aim of this study was to find out the potency of Erionota thrax to spread Blood Disease Bacterium the causal agent of banana blood disease in Indonesia. A field survey was conducted to record the existance of Blood Disease Bacterium in larvae and adult E. thrax. The results show that Blood Disease Bacterium was not found in the larval stage of E. thrax. In the adult of E. thrax, the pathogen was found on the legs, wings, body surface, head and head surface, but it was not found inside the body of E. thrax

Pengimbasan Ketahanan Pisang Terhadap Penyakit Layu Bakteri (Raistonia solanacearum) Dengan Pseudomonas Cepacia =Induced Resistance of Banana to Bacterial Wilt (Ralstonia solanacearum) using Fseudomonas cepacia

Abstract Bacterial wilt caused by Ralstonia solanacearum (synonym Pseudomonas solanacearum E.E Smith.), have been an important disease of banana plants. The objective of this study was to know the ability of P. cepacia in inducing resistance and salicylic acid content on phytoalexin extract of banana plants. The result showed that resistance of Ambon Kuning cultivar could be induced by viable and extraselulair protein of P. cepacia. The induced banana plants had lower disease intensity than uninduced plants. Salicylic acid content in phytoalexin extract from banana was induced by extraselulair protein of P. cepacia was 41,41 ppb. Keywords: induce resistance - salicylic acid

Potensi Bakteri Endofit Asal Tanaman Pisang Klutuk (Musa balbisiana Colla) Sebagai Pendukung Pertumbuhan Tanaman

AbstrakBakteri endofit yang terdapat di tanaman pisang Klutuk dan keterkaitannya dengan sifat ketahanan tanaman pisang Klutuk pada cekaman biotik dan abiotik belum dilaporkan dalam publikasi ilmiah. Sebanyak 93 isolat bakteri endofit telah diperoleh dari pisang Klutuk, tetapi belum diketahui kemampuannya sebagai pendukung pertumbuhan tanaman (PPT). Penelitian ini bertujuan untuk mengetahui karakter isolat-isolat bakteri endofit dari pisang Klutuk sebagai pendukung pertumbuhan tanaman. Kelompok bakteri Gram positif dan negatif ditentukan dengan metode pewarnaan Gram. Kemampuan memfiksasi nitrogen (N2), memproduksi asam indol asetat (AIA), dan antagonisme terhadap Fusarium oxysporum f. sp. cubense (Foc) diuji untuk mengetahui kemampuan isolat bakteri endofit sebagai pendukung pertumbuhan tanaman. Hasil penelitian menunjukkan bahwa 87,10% isolat bakteri endofit dari tanaman pisang Klutuk merupakan kelompok bakteri Gram negatif dan 82,80% (77 isolat bakteri) menunjukkan karakter tunggal atau ganda sebagai PPT. Di dalam kelompok isolat tersebut, terdapat berturut-turut 60, 38, dan 20 bakteri yang mampu memfiksasi N2, menghasilkan AIA, dan antagonisme terhadap Foc. Hasil pengujian ini menunjukkan bahwa bakteri endofit dari pisang Klutuk didominasi oleh bakteri kelompok Gram negatif yang memiliki kemampuan sebagai pendukung pertumbuhan tanaman.Abstract The role of endophytic bacteria on the biotic and abiotic resistance of Klutuk banana plants has never been reported. A total of 93 endophytic bacterial isolates were obtained from Klutuk banana plants in a previous study, but their potency as Plant Growth Promoting Bacteria (PGPB) is not elucidated. This study aims to characterize those 93 endophytic bacterial isolates. Gram staining was performed to differentiate between Gram-positive and negative bacteria among the isolates. The ability to fix nitrogen (N2), produce indole acetic acid (IAA) and antagonize Fusarium oxysporum f. sp. cubense (Foc) were also examined to determine their potency as PGPB. The results showed that 87.1% of the endophytic bacterial isolates were Gram-negative bacteria and 83.87% (78 bacterial isolates) had single or multiple traits of PGPB. Among the isolates, 60, 38, and 20 bacteria were able to fix N2, produce IAA, and antagonize Foc, respectively. The results indicated that the endophytic bacteria inhabiting Klutuk banana plant are dominated by Gram-negative PGPB

Pengaruh Substitusi Pakan Alami (Tubifex) Dan Buatan Terhadap Pertumbuhanikan Tilan Lurik Merah (Mastacembelus Erythrotaenia Bleeker, 1850) [Effect of Substitusion of Life Food (Tubifex) with Artificial Food (Pellet) to Fire Eel (M. Erythrotaenia) Growt Rate]

Penelitian bertujuan untuk mengetahui pengaruh penggantian pakan alarai dengan kombinasi pakan alami dan buatan terhadap pertumbuhan dan sintasan ikan tilan merah. Penelitian dilakukan di Laboratorium Instalasi Penelitian Perikanan Air Tawar Depok selama 3 bulan dengan menggunakan akuarium ukuran 60x30x40 cm diisi air 40 liter, masing-masing 5 ekor setiap wadali. Berat awal ikan 17-18 gram. Pakan yang diberikan cacing Tubifex sp. dan pakan buatan berkadar protein 40 %. Kombinasi pelet dalam perlakuan adalah: A. Pemberian pakan 100 % cacing tubifex; B. Pemberian pakan 75 % cacing tubifex + 25 % pakan buatan; C. Pemberian pakan 50 % cacing tubifex + 50 % pakan buatan dan D. Pemberian pakan 25 % cacing tubifex + 75 % pakan buatan. Jumlah pakan dihitung berdasarkan berat kering sebanyak 7 % BB/hari diberikan 3 kali. Dari hasil penelitian menunjukkan bahwa kombinasi pakan alami cacing tubifex dan pakan buatan berpengaruh nyata (P<0,05) terhadap bobot mutlak individu, Iaju pertumbuhan dan sintasan. Kombinasi pakan masih layak untuk pemeliharaan ikan hias adalah 50 % cacing tubifex + 50 % pelet dengan bobot mutlak 5,75 gram, laju pertumbuhan harian 0,46 % dan sintasan 100 % dengan konversi pakan 4,65

Hubungan antara Aktivitas Poligalakturonase dengan Virulensi RAS 4 Fusarium Oxysporum F.sp. Cubense

One of the major constraints of banana plantation in Indonesia is the occurrence of fusarium wilt disease caused by Fusarium oxysporum f.sp. cubense. The pathogen produced series of cell wall degradation extracellular enzymes which have important roles in pathogenicity. Many studies have been conducted to know the role of degrading enzyme banana pectin is the major component of cell wall. Many pectinolytic enzymes such as polygalacturonase and others have been isolated from many fungal plant pathogens. The study was aimed to know the role of polygalacturonase towards the virulence of race 4 of F. oxysporum f.sp. cubense. The result showed that from 10 isolates of race 4 of F. oxysporum f.sp. cubense, the most virulent isolate was Lmp1 followed by Srg1, Bgl6, Mln1, Bgl3, A13, Bnt2, Gnk3, Kjg1 dan Wsb5. This was indicated by high and low percentage of wilting leaves of banana cultivar Cavendish when they were inoculated with these isolates. Incubation period varied from 3 to 6 weeks after inoculation SDS-PAGE showed that polygalacturonase, mostly PG1 and PG2, was secreted by these isolates, whereas PG3 was only found in growing cultures of Gnk3 and Wsb5 isolates. Detection of polygalacturonase activity with diffusion agar and reducing sugar methods showed that the activity of polygalacturonase secreted by F. oxysporum f.sp. cubense in the growing culture had no correlation with the virulence of the fungal pathogen. Salah satu kendala utama dalam budidaya pisang di Indonesia adalah gangguan penyakit layu fusarium yang disebabkan oleh jamur Fusarium oxysporum f.sp. cubense. Jamur patogen ini menghasilkan serangkaian enzim ekstraselular pendegradasi dinding sel yang berperan dalam patogenesis. Beberapa penelitian telah dilakukan untuk mengetahui peran enzim yang mendegradasi pektin, yang merupakan komponen penting dinding sel tanaman. Beberapa enzim pektinolitik seperti poligalakturonase dan yang lainnya telah berhasil diisolasi dari berbagai spesies jamur penyebab penyakit tanaman. Penelitian ini bertujuan untuk mengetahui peranan poligalakturonase terhadap virulensi ras 4 F. oxysporum f.sp. cubense. Hasil penelitian menunjukkan bahwa dari 10 isolat F. oxysporum f.sp. cubense, yang mempunyai virulensi tertinggi hingga yang terendah berturut-turut adalah Lmp1, Srg1, Bgl6, Mln1, Bgl3, A13, Bnt2, Gnk3, Kjg1 dan Wsb5. Hal ini ditunjukkan dengan tinggi-rendahnya nilai persentase daun layu yang ditimbulkan oleh isolat-isolat tersebut pada bibit pisang kultivar Cavendish. Masa inkubasi bervariasi dari 3 hingga 6 minggu setelah inokulasi. Uji SDS-PAGE menunjukkan bahwa pada filtrat pertumbuhan isolat jamur-jamur patogen ini disekresikan poligalakturonase (PG) terutama PG1 dan PG2, sedangkan PG3 hanya dijumpai pada filtrat pertumbuhan isolat Gnk3 dan Wsb5. Adapun hasil deteksi aktivitas poligalakturonase dengan metode difusi agar serta gula reduksi menunjukkan bahwa aktivitas poligalakturonase yang disekresikan oleh F. oxysporum f.sp. cubense di dalam filtrat pertumbuhannya tidak berhubungan dengan virulensi jamur patogen tersebut

Characterization of Pantoea Ananatis Isolated From Garlic and Shallot

The new disease on garlic (Allium sativum) and shallot (A. cepa L. aggregatum group) have been found in several production centers of garlic and shallot in Tawangmangu and Temanggung, Central Java. The infected plants showed symptoms of leaf blight accompanied by chlorosis. The objective of this study was to determine the pathogen that causes leaf blight and chlorosis based on the phenotypic characterization and gyrB gene sequences analysis. The research started from the isolation of pathogen, physiological and biochemical test, DNA extraction, and sequence analysis of gyrB using gyrB 01-F and gyrB 02-R primer. The results showed that the isolated bacterial pathogen have a yellow pigment, slimy colonies with regular borders, convex, gram-negative, non-spore, facultative anaerobic, motile, catalase production, indole production, and acid production from D-glucose, D-mannitol, sucrose, and lactose. From the pathogenicity test, it was found that the bacteria produced the typical symptom of leaf blight. Characterization of pathogens based on gyrB gene sequence revealed that the pathogen was placed in the group of Pantoea ananatis. IntisariPenyakit baru pada bawang putih (Allium sativum) dan bawang merah (A. cepa L. aggregatum group) telah ditemukan di beberapa sentra produksi bawang putih dan bawang merah di Tawangmangu dan Temanggung, Jawa Tengah. Tanaman yang terinfeksi menunjukkan gejala hawar daun disertai klorosis. Tujuan penelitian untuk mengetahui karakter patogen berdasarkan fenotipik dan sekuen gen gyrB. Penelitian dimulai dengan isolasi bagian tanaman yang sakit, uji fisiologi dan biokimia, ekstraksi DNA dengan metode CTAB/NaCl dan amplifikasi gen gyrB menggunakan primer gyrB 01-F and gyrB 02-R. Hasil uji menunjukkan koloni berlendir, cembung, pigmen berwarna kuning, gram negative, tidak berspora, aerob fakultatif, motil, produksi katalase, indol, membentuk asam dari D-glukosa, D-monnitol, sukrosa dan laktosa, dan patogenesitas positif. Karakterisasi patogen berdasarkan sekuen gen gyrB, menunjukkan patogen hawar daun berkerabat dekat dengan Pantoea ananatis