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Basal plate rot disease is one of the critical diseases in shallot plants. Control using synthetic chemical fungicides is still unable to overcome this problem, and it hurts the environment and reduces the population of essential microbes in plants. Endophytic actinomycetes have potential as biocontrol agents. They are reported to be able to inhibit the growth of pathogens, induce plant resistance, produce cell wall degrading enzymes, and promote growth. This research aims to obtain endophytic actinomycete isolates that have the potential to inhibit the growth of the fungus Fusarium. oxysporum f.sp. cepae causes of basal plate rot disease in shallot, and evaluate its inhibitory mechanism. Endophytic actinomycetes were isolated from tubers and roots of Liliaceae plants collected from shallots-production center area. The isolate obtained was tested for biosafety and continued with its inhibitory effectiveness against the fungus F. oxysporum f.sp. cepae in vitro, ability to induce resistance, and plant growth promotion test. The six best isolates were selected based on weighting using AHP and identified molecularly. The endophytic actinomycetes of Liliaceae plants can inhibit the growth of F. oxysporum f.sp. cepae up to 63.49% with an antibiosis mechanism, producing chitinase enzymes that cause lysis, induce resistance, and produce growth hormones such as IAA. Streptomyces sp. can inhibit the fungus F. oxysporum f.sp. cepae causes basal plate rot disease on shallot by producing antifungal compounds and chitinase enzymes, inducing resistance, and producing growth hormone.

Bawang merah adalah salah satu komoditas hortikultura unggulan di Indonesia. Salah satu kendala produksi bawang merah di Indonesia adalah penyakit busuk pangkal yang disebabkan oleh Fusarium oxysporum. Beberapa mikrob endofit telah dilaporkan perannya sebagai agens hayati dan efektif menekan penyakit tanaman. Penelitian ini bertujuan mengetahui kemampuan Bacillus siamensis, Chaetomium sp., Cuvularia lunata, dan Trichoderma asperellum dalam menekan pertumbuhan F. oxysporum. Mikrob endofit merupakan koleksi Departemen Proteksi Tanaman, Institut Pertanian Bogor. Pengujian secara in vitro dilakukan dengan metode uji koloni ganda dan uji produksi senyawa organik volatil (SOV) anticendawan dengan metode tangkup. Pengujian SOV dilakukan pada medium ADK dan TSA dengan tingkat konsentrasi, yaitu 20%, 40%, 60%, 80%, dan 100%. Uji in vivo dilakukan dengan menanam umbi bawang merah setelah direndam dalam suspensi mikrob endofit, kemudian dilakukan inokulasi F. oxysporum pada 1 minggu setelah tanam. Hasil uji koloni ganda menunjukkan hambatan sebesar 51.41% (B. siamensis), 71.04% (Chaetomium sp.), 69.45% (C. lunata), dan 74.55% (T. asperellum), sedangkan uji produksi SOV menunjukkan nilai THR yaitu 34.45% (B. siamensis), 14.53% (Chaetomium sp.), 35.23% (C. lunata), dan 42.57% (T. asperellum). Penghambatan insidensi penyakit oleh mikrob endofit pada uji in vivo berkisar 60.00% sampai dengan 73.33%.

Infection of Phytophthora infestans at high altitudes in tropical regions causes symptoms of tomato late blight throughout the year. Even though it is very easy to find in the field, P. infestans is often very difficult to isolate aseptically in the laboratory. This study aims to evaluate direct isolation techniques that can increase the success of isolating P. infestans. Isolation was carried out on a non-specific medium, consisting of potato dextrose agar (PDA), corn meal agar (CMA), oatmeal agar (OMA), and water agar (WA) with three alternative types of antibiotics, i.e. chloramphenicol, amoxicillin, and rifampicin. Observations were carried out to determine the effect of the medium on sporangia induction and the age of the original colony’s growth in CMA and OMA media. The results showed that the isolation of P. infestans using the direct method was successfully carried out on non-specific PDA, CMA, OMA and WA medium. The highest isolation success rate was obtained on CMA medium with the addition of 50 mg L-1 rifampicin. The fastest sporangia induction (8 days) was shown by colonies grown on OMA medium with the addition of 50 mg L-1 rifampicin based on the category of abundant sporangia after 20 days of incubation. Rejuvenation of P. infestans colonies for research purposes in the laboratory is recommended to be carried out routinely twice a month. This research provides practical guidance for understanding the bioecology of P. infestans infecting tomato plants, especially for further study on oomycetes fungi.

Streptomyces spp. telah banyak diteliti sebagai agens pengendali hayati penyakit tanaman karena kemampuannya dalam menghasilkan berbagai jenis antibiotik, terutama senyawa-senyawa anticendawan. Aplikasinya untuk pengendalian Fusarium oxysporum f. sp. cepae penyebab penyakit busuk fusarium pada bawang merah di Indonesia belum dieksplorasi. Penelitian ini bertujuan mengevaluasi efektivitas Streptomyces spp. dalam mengendalikan F. oxysporum f. sp. cepae serta senyawa apa saja yang dihasilkan. Pengujian yang dilakukan meliputi uji efektivitas Streptomyces spp. terhadap pertumbuhan bawang merah dan insidensi penyakit busuk fusarium, serta analisis senyawa yang dihasilkan oleh Streptomyces spp. Hasil pengujian menunjukkan bahwa Streptomyces spp. tidak dapat meningkatkan parameter pertumbuhan. Sementara itu, pemberian Streptomyces spp. mampu menekan insidensi penyakit busuk fusarium dan memperpanjang masa inkubasi patogen. Analisis ekstrak kasar S. lydicus ABF 59 menunjukkan terdapat lima senyawa dominan yang bersifat anticendawan yaitu, d-limonene, tridecane, o-cymene, 2,4-di-tert-butylphenol (2,4-DTBP), dan hexadecanoic acid, methyl ester.

Nematoda daun Aphelenchoides fragariae mempunyai inang yang luas dan dapat berperan sebagai parasit tumbuhan maupun pemakan cendawan. Belum ada informasi terkait teknik perbanyakan A. fragariae di Indonesia. Penelitian untuk memperoleh jumlah nematoda A. fragariae yang murni perlu dilakukan untuk mendukung penelitian di masa mendatang. Penelitian ini bertujuan untuk memperbanyak A. fragariae menggunakan biakan cendawan pada tiga suhu yang berbeda dan menghitung jumlah nematoda. Biakan cendawan yang digunakan ialah, Alternaria porri, Botrytis cinerea, Fusarium oxysporum f. sp. cepae, Pythium sp., dan Rhizopus sp. Lima spesies cendawan tersebut diinkubasikan pada tiga suhu. Untuk memperoleh kondisi yang sesuai, biakan cendawan diinkubasi pada tiga suhu yang berbeda. Sebelum ditumbuhkan dalam biakan cendawan, nematoda dicelupkan ke dalam larutan streptomisin sulfat 0.1%, kemudian dicuci menggunakan air steril. Selanjutnya, 20 nematoda steril diinfestasikan pada biakan cendawan berumur 7 hari dan diinkubasi pada suhu 16, 28, dan 37 ℃. Setelah 28 hari, nematoda dipanen dan dihitung jumlahnya. Di antara spesies cendawan yang diuji sebagai media pemeliharaan, biakan terbaik untuk reproduksi A. fragariae ialah Alternaria porri pada suhu 28 ℃, dengan jumlah nematoda akhir rata-rata hingga 407.8 per cawan petri Pada suhu 37 ℃ A. fragariae gagal bereproduksi di semua biakan cendawan yang diuji. Hal ini menunjukkan bahwa di antara ketiga suhu tersebut, yang paling mendukung pertumbuhan dan perkembangan nematoda ialah 16 dan 28 ℃, yang paling tidak mendukung adalah 37 ℃.

White root disease is a significant disease of cashew caused by Rigidoporus sp. Five endophytic fungal isolates, namely AR31D (Fusarium proliferatum), AR42D (Penicillium citrinum), BR32C (Trichoderma asperellum), VNTB1 (Chaetomium sp.), and EAGS14 (Curvularia lunata), were assessed as the biocontrol agents against Rigidoporus sp. in vitro and in planta. The research objective was to obtain endophytic fungi that effectively control Rigidoporus sp. and their mechanisms. The in vitro test results showed that all isolates could inhibit Rigidoporus sp. and promote plant growth by producing volatile organic compounds, chitinase enzymes, and indole acetic acid. Meanwhile, only four isolates could solubilize phosphate with low-medium solubilization efficiency. The isolates successfully colonized the root of cashew saplings in 10-65%. The effectiveness of endophytic fungal isolates in controlling white root disease was determined by the mechanisms involved, such as resistance induction (increased activity of defense enzymes like polyphenol oxidase), chitinase enzyme production, indole acetic acid production, phosphate solubilization, and suppression of plant stress which observed from decreased malondialdehyde concentrations in saplings' roots. Trichoderma asperellum and Chaetomium sp. were the best isolates with the highest control effectiveness and stimulating plant growth.

As an archipelago regency, the Sangihe Islands has been known for its expanses of coconut plantations, which are one of the local community's primary commodities and sources of income. An inventory of pests and diseases specific to coconut in this area has never been carried out, and this information is needed, especially regarding sustainable coconut management. This study aimed to determine the presence of coconut pests and diseases in Sangihe and to obtain the latest conditions related to pests and disease incidence. The research was carried out through several stages, i.e., interviewing farmers, sampling, and identifying and documenting pests and diseases. The climate condition of Sangihe Island is classified as type A (very wet), with an average rainfall of 248 mm, temperature of 27 C, and humidity of 83% from 2017-2021. This condition is one of the determining factors for the existence of pest attacks and disease-causing pathogen infection on coconut. Pests dominated as disturbing organisms compared to diseases caused by plant pathogens. These pests included grasshoppers, coconut rhinoceros beetles, coconut hispine beetles, coconut mites, and white-tailed mice. Observations of the damage intensity by Sexava coriaceae were conducted in the Tahuna Barat district by selecting three land categories. The most severe damage occurred in field B (mostly planted with Hybrid Coconuts) with a percentage of 39%, while the lowest damage was in field C (mostly planted with Tall Coconuts), at 17%. The major disease detected was a gray leaf spot caused by the fungus Pestalotiopsis palmarum. The highest disease incidence and severity were found in Tabukan Utara district with percentages of 43% and 22% respectively, while the lowest incidence and severity were found in Tahuna Barat district with percentages of 3% and 1%, respectively.

Hot Water Treatment and Plant Growth Promoting Rhizobacteria to Suppress Seed-Borne Fungi on Rice Variety IPB-3S IPB-3S is a new rice variety which was developed to improve national rice production in Indonesia. This study aimed to determine seed-borne fungi associated with IPB-3S variety and to determine the potential of hot water and PGPR treatment to suppress the fungal infection. The study consisted of five experiments, i.e. seed health test by dry seed observation and by blotter test, pathogenicity test, seed treatment using hot water and plant growth promoting rhizobacteria (PGPR). Seven genera of fungi were found in IPB-3S seeds, namely Aspergillus, Penicillium, Rhizopus, Rhizoctonia, Curvularia, Fusarium and Colletotrichum. All of these fungi are pathogenic based on pathogenicity test. Seed treatment using hot water at 54 ℃ and PGPR reduced fungal infections and increased germination of IPB-3S seeds.

Penyakit bercak cokelat sempit pada tanaman padi menjadi salah satu penyakit yang paling merugikan. Di Indonesia, informasi mengenai penyakit ini masih terbatas dan kurang mendapatkan perhatian petani dan peneliti. Pengetahuan dasar mengenai patogen penyebabnya—Cercospora janseana—diperlukan sebagai acuan dalam tindakan pengendalian dan memahami epidemiologinya di masa mendatang. Penelitian ini bertujuan menentukan teknik isolasi yang sesuai untuk C. janseana serta melakukan karakterisasi morfologinya dari beberapa varietas tanaman padi. Teknik isolasi yang digunakan ialah metode penanaman jaringan, suspensi spora, penyebaran spora, dan penempelan spora. Pengamatan morfologi dilakukan dengan mengamati warna dan pertumbuhan koloni, konidium dan konidiofor, serta pertumbuhan koloni pada medium tumbuh yang berbeda. Hasil penelitian menunjukkan bahwa teknik isolasi yang sesuai untuk C. janseana ialah dengan penempelan spora pada agar-agar air dan menumbuhkannya pada medium agar-agar Martin. Teknik ini lebih baik dibandingkan dengan tiga teknik isolasi lainnya dan berhasil memudahkan proses isolasi C. janseana hingga diperoleh isolat murni.

The Severity of Fusarium Wilt Disease in Correlation to the Abundance of Fusarium oxysporum and Phytonematodes: Case Study at Banana Plantation PTPN VIII Parakansalak Fusarium oxysporum f. sp. cubense is a soil-borne pathogen that infects banana plants and causes wilt. Several studies demonstrated that phytomatodes have a role in helping infection of the pathogens that cause wilt. This study aims to determine the relationship between phytonematodes and Fusarium oxysporum f. sp. cubense from soil and banana roots infected with fusarium wilt. Soil samples was obtained from infected banana plants and collected based on different scores of fusarium wilt disease severity. Samples were then composited based on the score, and the abundance of each pathogen is measured following samples extraction in the laboratory. The highest population of phytonematodes was 77 g-1 obtained from soil with a disease severity score of 4; and the lowest was 16 g-1 from samples with a score of 2. As for root samples, the highest population of phytonematodes (85 g-1) was obtained from plants with a score 0 and the lowest (33 g-1) was from plants with a score 3. Two species of phytonematodes were identified, i.e. Helicotylenchus sp. and Radopolus sp. Based on measurement using conventional methods showed that the abundance of Fusarium oxysporum f. sp. cubense was highest in plants with a score of 1, i.e. 8.1 × 103 cfu g-1 soil and lowest in plants with a score of 0 i.e. 1.0 × 103 cfu g-1 soil. The effect of Fusarium oxysporum f. sp. cubense to the severity of fusarium wilt shows a positive relationship of 8.3% and it may contribute to cause fusarium wilt disease by 0.6%. This pathogen can cause wilting of bananas without the help of the phytonematode species found in this study.

Talas (Colocasia esculenta L. Schott) merupakan tanaman herba yang telah dimanfaatkan sebagai bahan pangan di beberapa wilayah di dunia. Tanaman ini dipercaya berasal dari Asia Tenggara (Lebot et al. 2010). Di Maybrat, Papua Barat talas telah dimanfaatkan sebagai tanaman bahan pangan pokok utama sejak dahulu oleh masyrakat lokal dan disebut dengan nama ‘Wiah atau Awiah’. Hingga awal tahun 2013, belum terdapat laporan yang memadai terkait serangan hama dan penyakit tanaman talas di daerah ini. Namun, pada pertengahan tahun 2013 petani setempat melaporkan adanya epidemi penyakit busuk umbi talas di pertanamannya. Tujuan penelitian ini ialah untuk membuktikan penyebab penyakit busuk umbi talas di Maybrat. Pengujian dilakukan secara in vivo dan in planta pada umbi dan tanaman talas. Dari 38 isolat cendawan yang diisolasi, 50% bersifat patogen. Tiga isolat yang terpilih (Y1, YP1, dan S4) mampu menyebabkan pembusukan jaringan umbi secara in vivo dan kerusakan akar secara in planta. Uji in planta menunjukkan bahwa inokulasi gabungan dua isolat dari ketiganya mampu menyebabkan kerusakan akar yang berat. Secara morfologi, isolat YP1 dan S4 diidentifikasi sebagai Fusarium oxysporum dan Y1 merupakan F. solani. Ini merupakan laporan yang pertama tentang penyakit busuk umbi talas dari Maybrat, Papua Barat.

Antraknosa merupakan penyakit penting pada tanaman cabai di Indonesia yang disebabkan oleh Colletotrichum acutatum. Antraknosa sangat merugikan karena menurunkan hasil produksi. Tujuan penelitian adalah mendapatkan cendawan laut yang berpotensi menghambat pertumbuhan C. acutatum dan menekan penyakit antraknosa, serta mengidentifikasi isolat cendawan laut yang potensial sebagai agens pengendalian hayati. Potensi agens hayati mengacu pada hasil penapisan seperti uji antagonis dan senyawa organik volatil (SOV), sedangkan penghambatan penyakit antraknosa pada cabai didasarkan pada hasil pengukuran insidensi penyakit dan diameter gejala antraknosa. Hasil uji menunjukkan semua isolat cendawan laut berpotensi menghambat pertumbuhan C. acutatum dan menghasilkan SOV, serta dapat menekan insidensi penyakit antraknosa pada cabai. Empat galur cendawan laut, yaitu 4145, B3st2, GN322, Z521 memiliki potensi menjadi agens pengendalian hayati penyakit antraknosa pada cabai. Hasil identifikasi empat galur tersebut berdasarkan analisis sikuen nukleotida adalah Fusarium proliferatum 4145, Trichoderma harzianum B3st2, fungal endofit GN322, dan Fusarium solani Z521.

Application of fungicides to control rice diseases potentially have adverse effect on non target organisms including endophytic fungi. Unfortunately, information of fungicide effect on endophytic fungi on rice is still limited. The purpose of this research was to study the diversity and abundance of endophytic fungi on rice plant because of application of synthetic fungicides. There were two treatments in this study: non systemic fungicide (mankozeb) and systemic fungicide (difenoconazole) which were compared to control (without fungicide). Isolation of endophytic fungi and application of fungicides were conducted every week started at aged of 3 to 10 weeks after planting. Variables observed were total segment of rice colonized by endophytic fungi, colonization frequency of endophytic fungi, continued by identification and analysis of the diversity of endophytic fungi. This study showed that there was an increase in colonization of endophytic fungi with an increase of plant ages. The diversity of endophytic fungi was higher in stems than in leaves with the value of H' is 0.001.35 and 0.000.98 respectively. The most common types of endophytic fungi appear in each isolation of rice segments were Acremonium, Curvularia, Fusarium, Helminthosporium, Nigrospora, Penicillium, and Mucor. Both fungicides do not significantly affect the percentage of colonization and diversity of endophytic fungi. At the beginning of planting (46 MST) there was a decrease in the percentage of endophytic fungal colonization in the stem. From the percentage of colonization of each genus of fungi, Nigrospora and Fusarium decreased significantly with difenoconazole on the stem during the vegetative phase.

Rhodotorula sp. is widely known as a biocontrol agent and is reported effective in controlling several diseases on crops. Rhodotorula minuta Dmg 16 BEP is an antagonist yeast from Indonesia which was effective in controlling various plant diseases. The objective of this research was to study the in vitro mode of action of R. minuta Dmg 16 BEP against Alternaria solani. The antibiosis ability of R. minuta Dmg 16 BEP to A. solani might be based on the activity of volatile compounds and not from its metabolites products. The growth of A. solani in paper disk assay and dual culture tests were not inhibited nor inhibitory zones developed, whereas the inverse petridish test showed the growth inhibition of A. solani. The results of the chitinolytic activity test on chitin agar and proteolytic on skim milk agar showed that no clear zone was formed. R. minuta has a strong hyperparasitic ability according to the slide culture test as the yeast cells surrounded A. solani hyphae and caused damage to some parts of hyphae.

Mancozeb is a group member of dithiocarbamat fungicides that most widely applied in the field. The use of mancozeb causes residues that have negative effects on agricultural production system and on agricultural environment. This research aimed to obtain dark septate endophyte (DSE) fungal isolates that are tolerant to mancozeb fungicide. The study was consisted of three steps, i.e., the isolation of DSE fungi from chili roots, the effect of DSE fungal isolates on chili seeds, and the growth ability of DSE isolates on medium supplemented with mancozeb. Thirteen DSE fungal isolates were isolated from chilli pepper roots and grown in the field assumed to be contaminated by pesticides. The isolates of DSE fungi caused the growth of chili seeds were normal and abnormal. Seven DSE isolates were able to grow well at PDA medium suplemented with mancozeb at concentrations of 100, 200, 400, and 800 ppm with different levels of relative growth inhibition. Mancozeb on PDA medium influenced the mycelial growth and colony color of DSE fungal isolates. The biomass of DSE fungal isolates were reduced when they were grown at malt extract broth (MEB) medium suplemented various levels of mancozeb.

Penyakit moler yang disebabkan oleh Fusarium oxysporum f. sp. cepae merupakan salah satu penyakit penting pada tanaman bawang merah. Aktinomiset memiliki potensi sebagai agens pengendali hayati F. oxysporum f. sp. cepae karena kemampuannya dalam memproduksi senyawa bioaktif. Penelitian ini bertujuan mengevaluasi dan menyeleksi isolat-isolat aktinomiset yang dapat menekan pertumbuhan F. oxysporum f. sp. cepae dan memacu pertumbuhan tanaman bawang merah. Penelitian dibagi menjadi empat tahap, yaitu: isolasi, seleksi, karakterisasi, dan identifikasi isolat aktinomiset yang potensial. Sebanyak 43 isolat berhasil diisolasi dari tanaman Liliaceae dan sebanyak 14 isolat berhasil diseleksi berdasarkan hasil uji keamanan hayati. Hasil uji antagonisme menunjukkan bahwa 14 isolat menghasilkan penghambatan terhadap F. oxysporum f. sp. cepae sebesar 3.67%–53.67%. Di antara 14 isolat tersebut, sebanyak 13 isolat mampu memproduksi enzim kitinase dengan indeks kitinolitik sebesar 0.31–1.38. Lima isolat terpilih yaitu: ABF42, ABF59, ACF45, AEF35, dan AEF45, mampu melarutkan fosfat dan memproduksi IAA dengan konsentrasi 24.82–82.88 ppm, namun hanya tiga isolat yang mampu memfiksasi nitrogen. Berdasarkan sikuen gen 16S rRNA, lima isolat tersebut berturut-turut teridentifikasi sebagai: Streptomyces rameus, S. lydicus, S. panaciradicis, S. seoulensis, dan S. fuscichromogenes.

We investigated the biocontrol activity of A. pullulans Dmg 30 DEP against Alternaria solani causal agent of early blight. Biocontrol activity was tested by the in vivo and ad planta. Biocontrol activity were tested by investigating the antibiosis capabilities with dual culture method, paper dish assay, two-compartment petri dish assay, and trapping and identification of volatile organic compounds (VOCs) with GC-MS. Lysis activity was examined by observing the clear zone formed by growing yeast on chitin agar and skim milk agar. The ability of hyperparasitism was assessed by the agar block method, and observed by light microscopy and scanning electron microscopy (SEM). The results showed that A. pullulans Dmg 30 DEP plays a role in the suppression of early blight disease at 106 cells/ml and 107 cells/ml yeast cell density. The mechanism involved in biocontrol activity is the production of VOCs, the production of chitinase and protease enzymes, the production of siderophore and hyperparasitism. The result shows that A. pullulans Dmg 30 DEP was colonizing the tomato leaves following the areole.

This survey was done in several guava fields around Bogor and found many unhealthy plants infested by various plant pests and diseases. This study aimed to analyze the effect of various guava cultivars on pest and disease intensity on guava in the Sub-District of Tanah Sareal, Bogor. Samples were collected from 20 fields that consisted of 15 samples of Getas Merah and 5 samples of Bangkok Putih cultivars to identify plant pests and diseases. Interviews were done with field owners to obtain information on cultivating practices. Pests found based on morphological identification included plant bugs (Hemiptera: Miridae), locusts (Orthoptera: Acrididae), bagworms (Lepidoptera: Psychidae), Geometrid caterpillars (Lepidoptera: Geometridae), Pyralid caterpillars (Lepidoptera: Pyralidae), scale insects (Hemiptera: Coccidae), planthoppers (Hemiptera: Flatidae), and mealybugs (Hemiptera: Pseudococcidae). Disease and pathogens identified included red rust disease (Cephaleuros sp.), anthracnose (Colletotrichum gloeosporioides), and fruit cancer (Pestalotia sp.). The occurrence of biting-chewing type pests was greater than piercing-sucking type insects, including 33.33% and 34.99%. Red rust disease was the dominant disease found on both guava cultivars consisting of 68.88% and 63.33% of the samples.

Aphelenchoides besseyi merupakan nematoda penyebab penyakit pucuk putih yang terbawa benih padi. Gen AB FAR-1 diketahui sebagai gen penting yang mengendalikan patogenisitas A. besseyi. Penelitian dilakukan untuk mengetahui karakter gen AB FAR-1 yang diisolasi dari nematoda yang berasal dari benih padi. Ekstraksi nematoda dilakukan dengan metode corong Baerman dari benih 5 varietas padi “Ciherang“, “Inpari Sidenuk“, “Sintanur“, “Hibrida Prima“ dan “Pak Tiwi“. Ekstraksi DNA total nematoda menggunakan metode CTAB dilanjutkan dengan amplifikasi gen AB FAR-1 menggunakan primer spesifik FAR-F1/R1 dan analisis urutan nukleotidanya. Pita DNA spesifik gen AB FAR-1 berukuran 150 pb berhasil diamplifikasi dari semua sampel nematoda. Analisis sekuen menunjukkan bahwa gen AB FAR-1 tersebut memiliki homologi tertinggi (92.5 – 100%) dengan aksesi Genbank JQ686690.1, yaitu gen AB FAR-1 A. besseyi asal Cina. Walaupun memiliki homologi yang tinggi, terdapat beberapa perbedaan nukleotida pada sampel gen AB FAR-1 A. besseyi asal “Ciherang“, “Inpari Sidenuk“ dan “Hibrida Prima“. Analisis pohon filogenetika lebih lanjut mengelompokkan gen AB FAR-1 A. besseyi menjadi 2 grup, yaitu grup 1 terdiri atas gen AB FAR-1 A. besseyi asal Cina, “Sintanur“, “Hibrida Prima“ dan “Pak Tiwi“ dan grup 2 gen AB FAR-1 A. besseyi asal “Ciherang“, dan “Inpari Sidenuk“.

Lasiodiplodia theobromae adalah cendawan patogen penting dan kosmopolitan di daerah tropis dan subtropis. Kisaran tanaman inangnya sangat luas, termasuk komoditas bernilai ekonomi tinggi di Indonesia, seperti jeruk, kakao, karet, pisang, dan manggis. Keragaman intraspesies galur cendawan hasil isolasi lima tanaman diamati berdasarkan pada ciri morfologi dan marka molekuler RAPD-PCR. Keragaman intraspesies ditunjukkan dari perbedaan laju pertumbuhan vegetatif koloni pada medium agar-agar dekstrosa kentang serta kemampuan menghasilkan struktur reproduksi. Galur cendawan asal jeruk, karet, dan pisang tumbuh cepat dan menghasilkan piknidium dan konidum pada medium agar-agar dekstrosa kentang dan medium agar-agar air yang dimodifikasi, sedangkan galur asal kakao dan manggis tumbuh lambat dan hanya dapat menghasilkan struktur reproduksi pada medium agar-agar air yang dimodifikasi. Keragaman antargalur dalam spesies L. theobromae ditunjukkan oleh perbedaan nyata morfologi struktur reproduksi. Konidium muda (tanpa sekat) memiliki panjang berkisar 13.5-25.7 μm, lebar 8.1-14.0 μm, dan nisbah panjang/lebar 1.5-2.2; sedangkan untuk konidium matang (bersekat) memiliki panjang 15.4-23.6 μm, lebar 10.7-12.8 μm, nisbah panjang/lebar 1.4-1.9. Walaupun ukuran konidium antargalur menunjukkan perbedaan, namun masih dalam kisaran ciri ukuran spesies L. theobromae. Profil fragmen DNA RAPD-PCR menggunakan primer tunggal OPB-01 maupun OPB-07 masing-masing menghasilkan jumlah dan ukuran pita DNA yang berbeda-beda antara lima galur sehingga menunjukkan adanya keragaman molekuler antargalur dalam satu spesies tersebut.

Extract of Piper betle as An Inhibitor of Anthracnose Postharvest Disease on Chili Pepper Chili is a horticultural commodity that mostly needed by consumers in the fresh condition. However, there is an interval of time needed to deliver it from producers (farmers) to consumers. During the supply chain, deterioration of the quality of chilli fruit can occur by the presence of anthracnose disease caused by Colletotrichum spp. The use of syntetic fungicides to control anthracnose disease is not recommended because it will leave residues that are harmful to consumers. The alternative that can be done is to use botanical pesticides as fungicides. The aim of this research is to study the potential of Piper betle leaves extract (PLE) in inhibiting the development of the antracnose disease caused by Colletotrichum acutatum on the chili during storage. The sequences of this research were strarted with production of PLE by boiling method which was preceded by blanching, chopping, and without treatment of betel leaves, then bioassay of betel extract by measuring the diameter of fungus growth on PDA+ PLE. The third test was application of PLE on fresh chili fruits by spraying and soaking, continued by observed the antracnoseinsidence on chili during storage time (21 days). The results showed that the chopping method was the best betel leaf extraction method among other treatments, the use of 10% PLE concentration was the most effective concentration in inhibiting the growth of C. acutatum in vitro, spraying treatment using 10% EDS was the most effective in inhibited the insidence of anthracnose disease.

Stem Canker: A New Disease of coffee in Lampung Stem cancer is a new disease that has attacked smallholder coffee plantations in Lampung since 2010. The cause of the disease was unknown. This study aims to describe the symptoms of the disease, the incidence of the disease in the affected plantation, and identify morphologically and molecularly the canker pathogens of the coffee stem canker diseases. All stages of Koch’s postulate were carried out in laboratories and greenhouses. The isolated pathogens were morphologically characterized by colony shape and color as well as the conidia shape and size. Molecular identification was carried out by using a general primer (ITS1 and ITS4) and followed by sequencing. The main symptoms of the disease are stem cancer and dieback, as well as more infecting older plants. Pathogen of the coffee stem canker disease that attacks coffee plants in Lampung has been identified as Fusarium solani which has 99% homology with F. solani KY245947.1.

Trichoderma and Gliocladium for Controling Fusarium Root Rot Disease of Oil Palm Seedlings Fusarium spp. have been reported as the causal agent of common spear rot and crown rot diseases on oil palm. An effective strategy to control these diseases is not available yet. This research was aimed to find biocontrol agents for effective control of crown rot disease on oil palm seedlings caused by Fusarium spp. The experiment consisted of 3 parts i.e. pathogenicity test of 3 isolates of Fusarium, identification and in vitro test of biocontrol agents, and in planta test of biocontrol agents against Fusarium spp. In vitro test was done through dual culture test and test for volatile compound produced by the biocontrol agents. In planta test was conducted through inoculation of Fusarium spp. into oil palm seedlings growing on medium containing selected biocontrol agents i.e. Trichoderma harzianum, T. virens, T. inhamatum, and Gliocladium fimbriatum. In vitro test showed that Gliocladium fimbriatum 1 and 2 were inhibited effectively the growth of Fusarium spp. on the dual culture test, whereas T. harzianum Gadingrejo 2 was inhibited effectively the growth of Fusarium spp. on volatile compound test. The application of biocontrol agents was effective to protect oil palm seedlings from Fusarium spp. infection.

Incidence of Viruses and Fungi on True Shallot Seed and Shallot Bulb Shallot is an important vegetable in Indonesia. Shallot farmers generally use bulbs as planting material even though there is an option to use true shallot seed (TSS). One important criteria for a good seed quality as planting material is pathogen free. Research was conducted to detect and identify viruses and fungi from TSS and shallot seed bulbs cultivars Bima, Bauji, Thailand, and Tuk-Tuk. Virus detection was carried out by DIBA (dot immunobinding assay) method using specific antiserum to OYDV, SLV, SYSV, and GCLV. Detection and identification of fungi was carried out by blotter test method and polymerase chain reaction. Infection of OYDV, GCLV, SYSV, and SLV were only detected in shallot bulbs with infection rates ranging from 66% to 100%. Four species of fungi were detected in TSS and bulbs, i.e. Aspergillus niger, A.flavus, F. solani, and Rhizopus sp; whereas F.oxysporum was only found in bulbs. All isolates of F. oxysporum was pathogenic and cause disease incidence up to 55%. Pathogenic isolate of F. oxysporum had 100% homology to those isolate from China and USA on the spesies level and 91.2% to those isolate from India and USA to the forma spesies level.

Identity of Botrytis Species on Horticultural Crops In West Java, Indonesia Botrytis species are economically important pathogens with a very broad host range including more than 200 horticultural crops. The identity of these fungus found in Indonesia has not been investigated and need to be reconfirmed due to the species variations of Botrytis found worldwide. The aims of this research were to identify Botrytis species infecting crops in West Java based on its morphology and molecular characteristics, as well as its pathogenicity traits. Based on morphological characters, all 25 isolates found were identified as B. cinerea. ITS-based sequences of the 8 isolates showed 96-100% similarity to reported B. cinerea in GenBank. The phylogenetic analysis confirmed that all collected B. cinerea were grouped in the same cluster with Australia, Netherlands, and other Asian region isolates. Pathogenicity tests using strawberry fruits demonstrated that all isolates were pathogenic as indicated by grey mold symptom development; the isolates from orchid showed the highest virulence. This research is the first report confirming Botrytis cinerea identity based on morphology and molecular methods in Indonesia, and also confirmed B. cinerea as the only species of Botrytis found in West Java.

The Effectiveness of Liquid Smoke and Electrotherapy to Eliminate Infection of Xanthomonas oryzae pv. oryzae in Rice SeedBacterial leaf blight caused by Xanthomonas oryzae pv. oryzae is a seed-borne disease that can reduce the productivity of rice. Alternative treatments that have not been widely developed is application of liquid smoke and electrotherapy. The aim of this research was to study the effectiveness of liquid smoke and electrotherapy and their combinations to eliminate X. oryzae pv. oryzae without damaging seed quality. The study consisted of three experimental stages: (1) Liquid smoke treatment on the viability of the bacteria and rice seeds; (2) Electrotherapy treatment on the viability of bacteria and rice seeds; (3) Combination of liquid smoke and electrotherapy treatment in bacteria-infected rice seed. The results showed that liquid smoke concentration (5% for 30 minutes) was able to reduce 83.33% population of X. oryzae pv.oryzae on rice seeds with 94.33% seed vigor, 98.00% germination, and time required to achieve 50% of total seed emergence (T50) of 3.13 days. Electrotherapy treatment (400 mA for 20 minutes) was not only eliminated X. oryzae pv. oryzae on rice seeds up to 100% but also maintained seed vigor 81.67%, germination 89.33%, and T50 3.47 days. Electrotherapy treatment (400 mA for 20 minutes) followed by immersion of infected rice seeds in liquid smoke concentration (1% for 30 minutes) could reduce 94.59% bacteria population while maintaining 86.00% seed germination. Treatment of electrotherapy (400 mA for 20 minutes) followed by immersion seeds into liquid smoke concentration (5% for 30 minutes) could reduce bacterial population up to 100%, but caused phytotoxicity effect to the seedling.

Blast disease (Pyricularia oryzae) in Indonesia is initially known to cause problem on upland rice, but since 2000’s blast disease was also reported occurred on lowland rice. Application of endophytic fungi is very potential to be used as disease control method. This study was conducted to isolates endophytic fungi from lowland rice, and determine its capability to reduce blast disease severity. Isolation of endophytic fungi was done from root, tiller, and the leaves of lowland rice. Kencana Bali variety was used for in vivo inhibition test due to its most susceptible response against P. oryzae. Forty seven endophytic fungi isolates were obtained from Bogor, Sukabumi and Blitar. Based on colony morphology, endophytic fungi can be differentiated into 9 morphotype. Four out of fourteen endophytic fungi showed antibiosis activity in in vitro inhibition test against P. oryzae. Inhibition test conducted on Kencana Bali variety in the green house showed that four isolates was able to suppress blast disease development by 30-70%.

Stem rot disease caused by Phytophthora capsici is an important disease on chilli. Eight endophytic fungi that had been isolated and screened based on pathogenecity test were further tested for their potential as the biological control agent of the stem rot disease of chilli. The endophytic fungi suspension was applied twice during the trial. The first application was on 100 seed lot, by soaking them in 100 mL of suspension. The second application was on the 3 weeks-old chili seedlings by drenching them with 10 mL suspension per plant. The concentration of endophytic fungi in the suspension was 2.8 × 106 cfu mL-1. The disease intensity and AUDPC value were measured for 4 weeks after the pathogen inoculation. The growth inhibition test of P. capsici was performed in vitro and the colonization abilities of endophytic fungi were observed at 4 weeks-old chilli seedlings. Eight endophytic fungi inhibited the growth of the P. capsici, and two of those isolates namely Penicillium strain MAG1 and Penicillium strain PAB2 showed antibiosis mechanism. Endophytic fungi has the ability more to colonize at the root (26–60%) than in the stem (20–40%). Fusarium strain MAGR1 has the highest level of endophytic colonization i.e. 60% compared to others. Based on in vivo assay, six endophytic fungi isolates, i.e. Fusarium strain MAGR1, Penicillium strain MAG1, Penicillium strain PAB2, sterile hyphae HAJ1, sterile hyphae HAJ2, and sterile hyphae PBG7, showed the potency to control stem rot disease with inhibition level of 25.5–35.5%

Wheat has a great potency to be cultivated in Timor Tengah Utara (TTU). However, disease is one of the risks for introduction of wheat. The existence of wheat disease in TTU is unknown because wheat has never been grown in this area. This study aims to determine the potential risks of major diseases that will infect wheat plants when introduced to the TTU. The methods used in this study consisted of wheat cultivation in the field, followed by observation and identification of the main diseases on wheat. Wheat varieties grown in field were Dewata, Selayar and Nias. Koch’s postulate were performed to identify the suspected microbes as pathogens. Morphological-based identification was applied on the isolated pathogens. The main diseases on wheat cultivated in TTU were leaf blight and stem rot. The results of Koch’s postulate showed that Helminthosporium gramineum was the causal of leaf blight and Rhizoctonia sp. was the causal of stem rot. Disease incidence reached 82–93% and 11–22% for leaf bligh and stem rot disease, respectively. Disease severity of leaf blight and stem rot disease on var. Dewata was the lowest compared to var. Selayar and var. Nias.

Pseudomonas fluorescens has been well known as biological control agent for plant diseases control. The problem to apply the agents widely in the field or in the level of farmer is limited technology of mass production with low cost, due to the simple technology of propagation has not been yet available. The objective of this research is to study the potency of liquid organic wastes as media for mass production of P. fluorescens and to formulate them as bio-pesticide. The results showed that modification of coconut water to pH of 7.0 could be used as media for growing P. flourescens. The P. fluorescens also could grow well in livestock liquid waste by adding 10% meat extract. On the other hand, the liquid tofu waste and liquid compost waste became good media for growing of P. fluorescens by addition of 10% meat extract and 1.25% sugar. Tetes tebu will be very good media for P. fluorescens at 5% final concentration and by adding of 10% meat extract and 2.5% of sugar. The P. fluorescens showed high antagonistic effect to Ralstonia solanacearum and Sclerotium rolfsii in all of modified liquid organic wastes media. Survival and antagonisctic activity of P. fluorescens in modified organic liquid wastes stored at 5oC or room temperature were 12 weeks. In vivo antagonistic and plant growth promoting activity showed that P. fluorescens grown in liquid organic waste suppressed the incidence of stem rot diseases caused by Sclerotium rolfsii and increased the vigor of plant growth on watermelon. Formulation of the P. fluorescens grown in modified coconut water gave the best performance of P. fluorescens in supppressing of plant diseases and inducing plant growth. The product of BeMOR(e) (beneficial microorganism) from the result of this research will be proposed to be patented

Endophytic fungi have been reported to have mutual symbiosis with their host. This research aimed to obtain nonpathogenic isolates of endophytic fungi from roots, stems, and branches of chili pepper. Endophytic fungi were isolated on 10% malt extract agar (MEA) after serial surface sterilization of plant parts. The effect of endophytic fungi on the development of chili pepper seeds were tested by growing seeds on media containing endophytic fungi isolate. As many as 138 isolates of endophytic fungi were successfully isolated from chili pepper plants from Garut and Bogor. Based on colony morphology the isolates can be differentiated into 9 morphotypes. Among the total isolates, 13.04% are nonpathogenic. Some of them (7,25%) do not effect seedling significantly compared to control and some isolates (5.79%) caused better seedling growth than control. Endophytic fungi having the potential to promote plant growth was identified as Aspergillus sp., Fusarium sp., Penicillium sp., sterile hyphae 1, 2, and 3.

Wilt disease of watermelon is an important disease in Indonesia, but determination of the causal agent has not been reported yet. Postulat Koch based approach was conducted to determine the pathogen causing wilt of watermelon from Karawang, West Java. Fungi associated with wilt symptoms were isolated from stem and root, then the fungal colonies were identified based on their morphological characters. Pathogenicity tests were performed using soil media and wet paper. Host range study involved other Cucurbitaceae plants, i.e. cucumber, melon and paria. Three species of Fusarium were successfully isolated from plants showing wilt symptom, i.e. F. oxysporum, F. solani, and F. semitectum. The fungus F. oxysporum consistently caused the most severe wilt symptom on watermelon, but developed no symptom on other tested cucurbits. The two fungi, F. solani and F. semitectum, caused necrotic on roots and stem of watermelon followed by wilting of the plant. The symptom was different than those of the initial symptoms from the field. Therefore it concluded that wilt symptom of watermelon is caused by Fusarium oxysporum f.sp. niveum. Key words: Cucurbitaceae, Fusarium oxysporum f.sp. niveum, species identification, wilt