Departement of Plant Protection

Microbe-intensive technology is an integrated package of various biocontrol agents in chili cultivation. This technology was known to be effective in suppressing various chili diseases. The effect of this technique on the two mayor pests of chili, i.e. fruit flies (Bactrocera sp) and thrips (Thrips sp) is still unknown. The aim of this study was to find out the effect of microbeintensive technology on the infestation intensity of fruit flies and thrips on chili pepper. The study consisted of four treatments, namely fully microbe- intensive, microbe- intensive in the nursery, conventional, and control. The research was conducted in three locations with different altitudes. Infestation intensity of fruit fly were observed at 10 and 11 weeks after planting, while observations of infestation intensity of thrips were carried out once a week from 2 to 10 weeks after planting. The application of microbe-intensive technology significantly reduced the infestation rate of fruit flies. Microbe...

Bacterial leaf blight control in rice (Oryza sativa Lin.) using bactericide is prohibitive, due to its high cost and its negative effect on the environment. Biocontrol when avaible, therefore is the best alternative solution. Bacillus subtilis is a perspective of biocontrol agent to control several plant diseases, because of its ability to produce antimicrobial and produce plant growth promoting substances. This research was aimed to examine the effectiveness of B. subtilis spore formulation by way of seed treatments and foliar sprays, using different frequencies and concentrations, to control bacterial leaf blight disease (BLB) on rice, caused by Xanthomonas oryzae pv. oryzae, and to evaluate its function as plant growth promoter. The experiments were conducted at greenhouse and in the field using factorial design. At the greenhouse experiment, seed treatment and foliar spray, using concentration of 2% produced better result in controlling BLB, and better result on promoting rice plant growth. In the field experiment, application at 2 week interval showed better effect on suppressing the the disease and on increasing yield. Applications of the formulation of B. subtilis B12 spore reduced BLB disease by 21% and potentially increased yield up to 50%.

Bakteri endofit sebagai agens biokontrol dapat dibuat formula untuk mempertahankan kemampuannya sebagai pengendali penyakit. Tiga isolat bakteri endofit yang mampu menekan serangan Meloidogyne sp. dan meningkatkan pertumbuhan lada telah diperoleh dari penelitian sebelumnya. Penelitian ini bertujuan mengevaluasi pengaruh lama penyimpanan formula tepung dalam mempertahankan viabilitas bakteri endofit dan karakterisasi fisiologi isolat endofit Bacillus sp. AA2, Bacillus sp. MER dan isolat MSJ. Formula yang digunakan ialah formula 1 (50 g talk, 1 g pepton, 0.5 g CMC, dan 1.5 g gula merah), formula 2 (50 g talk, 1 g pepton, 0.5 g CMC, dan 1.5 g gula putih), formula 3 (50 g talk, 1 g pepton, 0.5 g CMC, 1 g ekstrak khamir, dan 1.5 g gula putih dan) dan formula 4 (50 g talk, 1 g pepton, 0.5 g CMC, 1 g ekstrak khamir, 3 mL molase, 1 g bentonit, 0.75 g kalsium karbonat, dan 1 g dektrosa). Hasil karakterisasi bakteri menunjukkan bahwa isolat Bacillus sp. AA2 dan Bacillus sp. MER bersifat Gram positif, menghasilkan enzim kitinase, protease dan hormon IAA, sedangkan isolat MSJ menghasilkan enzim lipase dan hormon IAA. Sifat penambat nitrogen hanya ditemukan pada isolat Bacillus sp. AA2 dan isolat MSJ. Bakteri dengan viabilitas tertinggi adalah isolat MSJ, yaitu 2.5×10 6 cfu mL -1. dalam formula 4, sedangkan isolat Bacillus sp. AA2 dan Bacillus sp MER masing-masing 1.9×10 6 cfu mL -1. dan 1.2×10 6 cfu mL -1 dalam formula 3.

Berdasarkan hasil survei yang dilakukan pada pertanaman cabai di Desa Kertha, Kecamatan Payangan, Kabupaten Gianyar, Provinsi Bali, ditemukan banyak tanaman cabai dengan gejala klorosis yang disebabkan oleh virus. Tanaman sakit menunjukkan gejala kekuningan pada lamina daun, tetapi tulang daun tetap berwarna hijau. Usaha identifikasi difokuskan pada Pepper vein yellows virus (PeVYV) melalui penularan menggunakan Aphis nasturtii, pengamatan bentuk partikel virus, deteksi RNA total dengan reverse transcription-polymerase chain reaction (RT-PCR), dan perunutan sikuen nukleotida. Hasil diagnosis menunjukkan bahwa penyakit dapat ditularkan dari tanaman cabai sakit ke tanaman cabai sehat menggunakan A. nasturtii. Partikel virus berbentuk heksagonal dengan diameter berukuran ~30 nm. RT-PCR RNA total dari tanaman sakit bergejala berat, sedang, dan ringan menggunakan pasangan primer spesifik gen protein selubung PeVYV berhasil mengamplifikasi pita DNA berukuran ~650 pb. Sikuen gen protein selubung PeVYV isolat asal Bali dari intensitas gejala klorosis yang berbeda memiliki homologi tertinggi dengan PeVYV isolat Taiwan berkisar 95.1-96.6%. Dengan demikian, PeVYV dikonfirmasi sebagai penyebab klorosis pada pertanaman cabai di Bali, Indonesia. Kata kunci: Aphis nasturtii, Pepper vein yellows virus (PeVYV), protein selubung ABSTRACT Based on the results of a survey conducted on chilipepper plants in Kertha Village, Payangan Subdistrict, Gianyar District, Bali Province, many chilipepper plants with chlorosis symptoms caused by the virus was observed. Infected plants showed yellowing of the lamina, but the veins remain green.

Pepper vein yellows virus (PeVYV) isolat Bali telah berhasil diidentifikasi dari tanaman cabai bergejala klorosis. Oleh karena belum tersedia antiserum spesifik PeVYV komersial, untuk kepentingan deteksi perlu upaya membuat antiserum. Salah satu teknik terbaru dalam menyediakan sumber antigen untuk pembuatan antiserum ialah melalui teknik ekspresi gen protein selubung virus pada bakteri ekspresi yang sesuai. Gen protein selubung PeVYV berukuran ~650 pb diamplifikasi dengan primer spesifik, dikloning pada vektor ekspresi pQE30, ditransformasi dan dikayakan ekspresi gen tersebut (overexpression) pada bakteri ekspresi E. coli galur M15 [pREP4]. Analisis SDS-PAGE menunjukkan rekombinan gen protein selubung PeVYV berhasil terekspresi dengan pita protein berukuran ~25 kDa setelah 6 jam diinduksi dengan 0.5 mM IPTG pada suhu 37 °C.

Pustul bakteri yang disebabkan Xanthomonas axonopodis pv. glycines merupakan salah satu penyakit penting pada tanaman kedelai di Indonesia. Pengendalian umumnya dilakukan secara parsial sehingga hasilnya belum maksimal. Oleh karena itu, pengembangan alternatif pengendalian dengan memadukan berbagai komponen perlu dilakukan. Penelitian ini bertujuan menguji pengaruh pemberian mulsa jerami dan aplikasi PGPR terhadap keparahan penyakit pustul bakteri pada dua varietas kedelai di lapangan. Penelitian dilakukan di Desa Cigombong, Sukabumi, Jawa Barat. Rancangan percobaan yang digunakan adalah acak kelompok faktorial dengan tiga ulangan. Faktor perlakuan terdiri atas varietas kedelai, mulsa jerami, dan PGPR. Pengamatan terhadap keparahan penyakit pustul bakteri dilakukan setiap minggu. Hasil penelitian menunjukkan bahwa interaksi antara ketiga perlakuan tidak berpengaruh terhadap penekanan perkembangan penyakit (AUDPC), tetapi pengaruh varietas sangat nyata. Varietas kedelai Gepak Kuning lebih tahan (AUDPC= 99) dibandingkan dengan varietas Anjasmoro (AUDPC= 199). Perlakuan kombinasi varietas Gepak Kuning dan mulsa jerami (5 ton/ha) mampu menekan perkembangan penyakit pustul bakteri hingga 85.9% dibandingkan dengan perlakuan varietas Gepak Kuning tanpa mulsa jerami sehingga komponen pengendalian ini dianjurkan untuk diterapkan oleh petani.

Sapu pada kacang pinto (Arachis pintoi) adalah penyakit baru yang ditemukan di Bogor dalam kejadian yang cukup tinggi dan sejauh ini belum dilaporkan di Indonesia. Tipe gejala ini sangat mirip dengan gejala sapu kacang tanah (A. hypogea) yang telah lama diketahui disebabkan oleh fitoplasma. Penyakit sapu A. pintoi dapat ditularkan ke A. pintoi atau A. hypogea, demikian juga penyakit sapu A. hypogea dapat ditularkan ke A. hypogea atau A. pintoi dengan masing-masing gejala khas dan tidak berbeda, melalui uji penularan baik penyambungan maupun vektor spesifik fitoplasma sapu kacang tanah, Orosius argentatus. Tanaman A. pintoi maupun A. hypogea sakit terdeteksi berasosiasi dengan fitoplasma melalui teknik polymerase chain reaction menggunakan pasangan primer untuk fitoplasma P1/P7 dan menghasilkan pita DNA berukuran 1800 pb. Fitoplasma penyakit sapu A. pintoi diduga kuat identik dengan fitoplasma penyakit sapu A. hypogea.

Berdasarkan hasil survei yang dilakukan pada pertanaman cabai di Desa Kertha, Kecamatan Payangan, Kabupaten Gianyar, Provinsi Bali, ditemukan banyak tanaman cabai dengan gejala klorosis yang disebabkan oleh virus. Tanaman sakit menunjukkan gejala kekuningan pada lamina daun, tetapi tulang daun tetap berwarna hijau. Usaha identifikasi difokuskan pada Pepper vein yellows virus (PeVYV) melalui penularan menggunakan Aphis nasturtii, pengamatan bentuk partikel virus, deteksi RNA total dengan reverse transcription-polymerase chain reaction (RT-PCR), dan perunutan sikuen nukleotida. Hasil diagnosis menunjukkan bahwa penyakit dapat ditularkan dari tanaman cabai sakit ke tanaman cabai sehat menggunakan A. nasturtii. Partikel virus berbentuk heksagonal dengan diameter berukuran ~30 nm. RT-PCR RNA total dari tanaman sakit bergejala berat, sedang, dan ringan menggunakan pasangan primer spesifik gen protein selubung PeVYV berhasil mengamplifikasi pita DNA berukuran ~650 pb. Sikuen gen protein selubung PeVYV isolat asal Bali dari intensitas gejala klorosis yang berbeda memiliki homologi tertinggi dengan PeVYV isolat Taiwan berkisar 95.1-96.6%. Dengan demikian, PeVYV dikonfirmasi sebagai penyebab klorosis pada pertanaman cabai di Bali, Indonesia. Kata kunci: Aphis nasturtii, Pepper vein yellows virus (PeVYV), protein selubung ABSTRACT Based on the results of a survey conducted on chilipepper plants in Kertha Village, Payangan Subdistrict, Gianyar District, Bali Province, many chilipepper plants with chlorosis symptoms caused by the virus was observed. Infected plants showed yellowing of the lamina, but the veins remain green.

Rice is the main source of carbohydrates consumed by the Indonesian population. According to Badan Pusat Statistik, the average amount per capita rice consumption reached 113.5 kilograms in 2011. On the other hand, the population of Indonesia, which showed an increasing trend over the last decade, demands increased national rice production. In addition to quantity, the quality of rice,which is themost important factor in the consumption of rice, must be maintained. One way to achieve this is to manage rice diseases. In using the Integrated Pest Management (IPM) approach, the first step is to properly diagnose the rice diseases sothat the correct treatments can be taken up as soon as possible. However, in certain regions, experts may not be available to correctly identify the diseases. Computer vision can effectively solve this problem by rapidly identifying rice diseases through the employment of image processing techniques.We propose a new method of texture analysis to identify rice diseases using fractal fourier. In our studywe used the images of four rice diseases: bacterial leaf blight (Xanthomonas oryzae), blast (Pyricularia oryzae), brown spot (Helminthosporiumsp.) and tungro virus. The image of the rice leaf is converted to CIELab color space. The disease spots are then segmented using Otsu's threshold on ‘a’ component. The fractal descriptor of each spot is then estimated by using Fourier spectrum on ‘L’ component. The descriptor is then used to identify the disease using the probabilistic neural network. This method is able to achieve a 92.5% of accuracy. The experimental results showed that the proposed method is a promising technique to support IPM by the rapid identification of rice diseases.

The fungus Lasiodiplodia theobromae is an important and cosmopolitan pathogen in the tropics and subtropics. The range of host plants is very wide, including economic commodities in Indonesia, i.e. citrus, cocoa, rubber, banana and mangosteen. The intraspecies diversity of fungi isolates from those five plants from different provinces in Indonesia was observed based on the morphological characteristics and molecular markers of RAPD-PCR. The intraspecies diversity was shown from the vegetative growth rate of the colonies on PDA as a base medium and the ability to produce reproductive structures. The fungal isolates from citrus, rubber and banana were able to grow faster and produce pycnidium and conidium in both PDA and modified-WA medium, while the cocoa and mangosteen isolates grow slower and only could produce these reproductive structures in the WA medium. The diversity between isolates

The efforts to increasing the quantity and quality of rice production are obstructed by the paddy disease. This research attempted to identify the four major paddy diseases in Indonesia (leaf blast, brown spot, bacterial leaf blight, and tungro) using fractal descriptors to analyze the texture of the lesions. The lesion images were extracted manually. The descriptors of 'S' component of each lesion images then used in classification process using probabilistic neural networks. This techniques achieved at least 83.00% accuracy when identifying the diseases. This method has a potential to be used as one of the feature if it combined with other features, especially when two diseases with relatively same color involved.

has a wide host range including cultivated plants and weeds. Infected weeds may play an important role in disease epidemic. Unfortunately, little is known about weeds species that may serve as alternative host for . This research was conducted to identify on weeds around chili pepper field to study their potential role as virus reservoir. Field surveys were conducted to chilli pepper growing area in West and Central Java Provinces, and The Special Province of Yogyakarta during 2009 to collect symptomatic weed plants. infection was detected using PCR technique from 9 weed samples, i.e. 5 samples from Bogor (AgrBgr), Sukabumi (AgrSkm), Magelang (AgrMgl), Sleman (AgrJgy), and Garut (AgrGrt); from Magelang (CtpMgl); from Sleman (AcpJgy); from Bogor (PrlBgr); from Magelang (SplMgl). Further genetic analysis showed that those geminiviruses can be differentiated into 2 clusters, showing the possible genetic differences among them. They neither have a close relationship with other geminiviruses published earlier in the GenBank, indicating weed infecting collected in this study is possibly a distinct . Key words: , , polymerase chain reaction, weed species memiliki kisaran inang yang luas termasuk berbagai tanaman budi daya maupun gulma. Hingga saat ini pengetahuan tentang jenis-jenis gulma yang berpotensi menjadi sumber masih sangat terbatas. Penelitian ini dilakukan dengan tujuan mengidentifikasi pada gulma-gulma yang tumbuh di sekitar pertanaman cabai dalam upaya mempelajari perannya sebagai sumber inokulum virus. Survei lapangan telah dilakukan pada tahun 2009 ke beberapa daerah penanaman cabai di Provinsi Jawa Barat, Jawa Tengah, dan Daerah Istimewa Yogyakarta untuk mengumpulkan gulma-gulma yang menunjukkan gejala. Infeksi berhasil dideteksi menggunakan teknik PCR dari 9 sampel gulma, yaitu 5 sampel masing-masing dari Bogor (AgrBgr), Sukabumi (AgrSkm), Magelang (AgrMgl), Sleman (AgrJgy), dan Garut (AgrGrt) dari Magelang (CtpMgl), dari Sleman (AcpJgy), dari Bogor (PrlBgr), dari Magelang (SplMgl). Analisis genetika lebih lanjut menunjukkan bahwa yang menginfeksi gulma-gulma tersebut dapat dibedakan menjadi 2 kelompok besar yang merupakan indikasi adanya keragaman genetika di antara mereka. yang menginfeksi spesies gulma yang berbeda tersebut tidak memiliki hubungan kekerabatan yang dekat dengan geminivirus lain yang dilaporkan dalam sehingga yang diidentifikasi dari spesies gulma tersebut merupakan yang berbeda..

Phytophthora capsici infection of chili pepper seedlings can cause substantial losses due to damping-off and collar rot diseases. Chemical control is no longer effective due to reported resistance development, on top of the related environmental concerns and the consumer demands for reduced use of fungicides. Biological control is a sustainable option, with several agents having been reported to be effective against this pathogen. This research focused on optimizing the application of strain THSW13 of Trichoderma hamatum and a bacterial isolate BJ10-86 with the objectives of improving chili pepper seed germination, reduce damping-off disease incidence, and improve the growth of the seedlings. Bacterial isolate BJ10-86 was subjected to molecular identification and found to be Pseudomonas aeruginosa. Chili pepper seeds treated with the biocontrol agents, individually or in combination, were seeded into commercial nursery media that had been pre-inoculated with P. capsici zoospores. Over a period of 35 days the chili pepper seed treatments significantly (P = 0.008) reduced the disease incidence of seedlings damping-off. Combined application of T. hamatum and P. aeruginosa was the best biocontrol treatment with an area under disease curve of only 36.61 units compared to 92.87 units for the control treatment. Similar results were observed in vitro where T. hamatum and P. aeruginosa synergistically inhibited P. capsici growth by 73.2 %. The inhibition activity of this treatment was similar to mefenoxam treatment, which implies that it is an effective and sustainable alternative for chili pepper seed treatment. The biocontrol seed treatment had no effect on seed germination and seedling growth.

Pustul bakteri yang disebabkan Xanthomonas axonopodis pv. glycines merupakan salah satu penyakit penting pada tanaman kedelai di Indonesia. Pengendalian umumnya dilakukan secara parsial sehingga hasilnya belum maksimal. Oleh karena itu, pengembangan alternatif pengendalian dengan memadukan berbagai komponen perlu dilakukan. Penelitian ini bertujuan menguji pengaruh pemberian mulsa jerami dan aplikasi PGPR terhadap keparahan penyakit pustul bakteri pada dua varietas kedelai di lapangan. Penelitian dilakukan di Desa Cigombong, Sukabumi, Jawa Barat. Rancangan percobaan yang digunakan adalah acak kelompok faktorial dengan tiga ulangan. Faktor perlakuan terdiri atas varietas kedelai, mulsa jerami, dan PGPR. Pengamatan terhadap keparahan penyakit pustul bakteri dilakukan setiap minggu. Hasil penelitian menunjukkan bahwa interaksi antara ketiga perlakuan tidak berpengaruh terhadap penekanan perkembangan penyakit (AUDPC), tetapi pengaruh varietas sangat nyata. Varietas kedelai Gepak Kuning lebih tahan (AUDPC= 99) dibandingkan dengan varietas Anjasmoro (AUDPC= 199). Perlakuan kombinasi varietas Gepak Kuning dan mulsa jerami (5 ton/ha) mampu menekan perkembangan penyakit pustul bakteri hingga 85.9% dibandingkan dengan perlakuan varietas Gepak Kuning tanpa mulsa jerami sehingga komponen pengendalian ini dianjurkan untuk diterapkan oleh petani.