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Indonesian nutmeg export is constrained due to aflatoxin content that exceeds the minimum limit. This study was aimed at examining the effectiveness of three drying types of nutmeg to diminish aflatoxin contamination. The three drying types tested were (a) the rack type house with a source of solar energy heat combined with a kerosene stove fire, (b) the drying bases one meter above the ground with or without a black cloth cover, and (c) the floor drying 5 cm above the ground with or without black cloth cover. Unpeeled nutmegs were dried in the drying racks until they dried (sound when shaken by hand). After that they were. peeled and redried in the same type of dryer. Observation parameters included temperature, humidity, drying time, moisture content, oil content, oleoresin, myristicin, and aflatoxin content. The results showed that the drying time in the house-type drying rack was 51.5 hours, longer than the para-para and drying floor (30 hours). The temperature during drying in the drying house was 35.6-37.31 0 C lower than the other two types of dryers. However, its humidity was the highest (40.71-49.33%). The moisture content of shelled nutmegs and peeled nutmegs from all drying types fulfill the requirements (< 10%). The total aflatoxin contamination in shelled nutmegs and peeled nutmegs was < 3.28 µg/kg, while B1 aflatoxin was < 1.06 µg/kg, so that they fulfilled SNI standard. All three drying types can be recommended to be tested further in field scale. Keywords : Nutmeg, Myristica fragrans, drying technology, seed quality.

Carboxy methyl selulase and exo-polygalacturonase enzymes production and their role in determining the pathogenicity of Ralstonia solanacearum isolated from gingerBacterial wilt disease on ginger (Zingiber oicinale Roscoe) caused by Ralstonia solanacearum is the most destructive disease Infected tissues show macerated symptom on infected hosts indicating that the pathogen produces plant digestive enzymes. This research was aimed at analizing carboxymethylccllulasc (CMC-ase) and exopolygalacturonase (cxo-PG) enzymes production by the pathogen. In vitro production of CMC-ase of both virulent and avirulcnt isolates of R solanacearum was measured from diameter of clearing zone around bacterial colony on CMC medium whereas exo-PG was measured by the reduction of Na- polygalacturonatc by filtrate of the pathogen culture. Virulence of the pathogen was tested on tomato cultivar Gondol Hijau by pouring 50 ml of pathogen suspension (I07 cfu/ml) around roots of the plant and it was also tested on ginger cultivar Jahe Putih Besar by pricking suspension of pathogen into rhizome and basal pscudostcm of the plant. The results showed that CMC-ase and and PG-asc were produced by virulent isolates of R. solanacearum al 2.23 cm clear zone and 0.662 mg eq. glucose/ml/hour/ODiti, respectively. The avirulent isolates, however. correlated with disease intensity of the isolates. Disease intensity of the virulent isolates was 0.6 and 0.96 on tomato and on ginger plants respectively, whereas the avirulent isolates was 0.04 and 0.00 respectively. Therefore, CMC-ase and exo-PG are important in determining pathogenicity level of/?, solanacearum.

Potency of antagonist bacteria in inhibiting the bacterial wilt disease progress gingerBacterial wilt disease caused by Pseudomonas solanacearum is an important disease in ginger plant (Zingiber oicinale Rose.) in Indonesia. The objective of this research was to study the effectiveness of biological agents in inhibiting the progess of bacterial wilt on ginger. The research was conducted at the geenhouse of Research Institute for Spice and Medicinal Crops in 1997-1998 then was followed with a ield experiment at Sukamulya Experimental Garden in 1998/1999. At the greenhouse experiment seven kinds of antagonists bacteria were formulated either individually or combination. Pseudomonas fluorescens (PF), P. cepacia (PC) and Bacillus sp. (BC), mixtue of PF + PC, mixtue of PC + BC, mixture of PF + BC, and mixtue of PF + PC + BC were tested in the geenhouse on ginger plant cultivars putih besar grown in the pot containing soil formerly used for growing P. solanacearum infected tomato. I he results of this experiment indicated that the combination of PF+PC+BC significantly suppressed the progress of bacterial wilt disease compaed to control and other tested combination. In the ield experiment carried out at the bacterial wilt disease endemic area the combinations of PF+PC+BC, Trichoderma harzianum (Bit-1) and combination of PF+PC+BC+BII-I were tested with two levels of application, i.e. two applications with two months interval and 4 application with one month interval. The results showed that the application of antagonists bacteria inhibited Ihe bacterial wilt disease progress and signiicantly increased ginger rhizome yield. The yield of the rhizome from the plants teated with different intervals were not different. However, the application of the antagonist bacteria were not able to eradicate ginger infection by Pseudomonas solanacearum thoroughly.

Pestalotiopsis desseminata on cashew: its biology and interaction with Helopeltis antoniiPestalotiopsis desseminata is one of pathogens causing leaf spots. die-back of shoots and inflorescence of cashew plant. It is assumed there is an interaction between the attack of Helopeltis antonii and the fungus in Ihe ield so that the damage becomes more devastating. The objectives of (his research were to investigate several aspects of fungal biology (pathogenicity, mycelial growth, acervuli production, sensitivity to fungicides) and its interaction with //. antonii. The esearch was carried out from April 1999 to March 2000 at the laboratory and green house of Pest and Disease Department Research Institute for Spice and Medicinal Crops, Bogor. /' desseminata was diectly isolated from cashew leaves. Pathogenicity test of P. desseminata isolate was conducted on cashew seedlings. The fungal growth and fungicide effects were carried out in vitro on agar medium. The interaction between P. desseminata and H. antonii was examined by inoculating the fungus and insect, either individually or in combination, on cashew seedlings. The results showed that P. desseminata isolate fomis black spherical acervuli containing oblongs conidia with 5 cells, and the outermost cell has 3 flagellate. Acervuli could only be produced on the cultue illuminated continuously by 600 lux translucent lamp. Pathogenicity test of several isolates of /' desseminata on cashew seedlings caused spherical leaf spot symptom, individually or coalesced as bigger leaf spots. In vitro fungal mycelia growth could be suppressed by several fungicides, including bcnomyl 50% (I ppm) and Uiiopanate-mcthyl 70% (10 ppm) Combining inoculation between P. desseminata and //. antonii resulted in moe severe (devastating) die-back compared with individually inoculated.

The cause of stunting disease of black pepper (Piper nigrum) in Indonesia has not yet been confirmed cither due o a virus or mycoplaam. However, similar disease found on black pepper plants in the Southeast Asia is caused by Piper yellow mottle virus (PYMV) which is transmitted by Planococcus citri. This expeiments was aimed o examine the cause of the stunting disease and its insect vectors. The expeiment were conducted from October 1998 to May 2001. Diseased vegetative materials of black pepper plants showing stunting disease were collected from Sukamulya, Sukabumi. The potential insect vectors were collected from black pepper plants in Bogor, IP Sukamulya (Sukabumi), Lampung and Bangka. The insects were fed on the diseased plants obtained from Lampung, Bogor and IP Sukamulya, then transferred o the healthy plants. The healthy plants were produced rom true seeds and cutings oiginated rom Bogor and IP Sukamulya. The tested plants were incubated at the green house and examined for disease development. Diseased leaf samples collected rom black pepper plant rom IP. Sukamulya and the transmitted plants were sent to the University of Minnesota, USA for Ihe virus (PYMV) by using ISEM (immunosorbent electron microscope). The result snowed that the leaves samples rom IP. Sukamulya were infected by PYMV. The morphology and size of the virus were similar to those caused stunting disease in the South East Asia. Potential insects vectors found on the diseased black pepper plants were two mealybugs, P. minor and Ferrisia virgata (Hemiptera; Coccoidca: PaaidbcoccidaeX aa well as an aphid Toxoptera aurantii (Hemiptera: Aphidoidea: Aphididae). The first tial on disease transmission by using P. minor, previously reared on the potato tubers, showed one out of ten tested plants produced disease sympom. The subsequent trial using P minor, bred on healthy black pepper seedlings, showed thee out often tested plants developed disease symptoms. None of the aphid transmitted plants developed Ihe disease. This study confirmed thai PYMV b the cause of stunting disease on black pepper in IP Sukamulya and Lampung and P. minor as the insect vecor of the disease.

Nematoda hawar daun Aphelenchoides sp. telah dilaporkanmenyerang dan menyebabkan gugur daun pada sambiloto (Andrographispaniculata (Burm. f.) Wall. ex Nees) (Acanthaceae). Penelitian yangbertujuan untuk mengindentifikasi spesies Aphelenchoides sp. tersebuttelah dilakukan di laboratorium, rumah kaca dan kebun percobaan BalaiPenelitian Tanaman Obat dan Aromatik pada tahun 2005-2006.Identifikasi dilakukan dengan mengamati gejala khas pada tanaman sakitdan karakteristik morfologi nematoda secara mikroskopik pada preparatsemi-permanen Aphelenchoides sp. yang difiksasi dengan larutantriethanolamine formaldehyde (TAF). Gejala khas hawar daun merupakanbercak klorotik yang meluas yang kemudian berubah berwarna kehitamanatau kadang-kadang keunguan yang dibatasi tulang-tulang daun. Secaramikroskopik bentuk tubuh betina Aphelenchoides sp. ramping denganpanjang tubuh berkisar 0,46 – 0,70 mm dan lebar tubuh rata-rata 15 µm;daerah vulva terletak 2/3 dari panjang tubuh diukur dari bagian anterior;stilet ramping, panjangnya 10 µm dengan “basal knobs” kecil tetapi jelas;metakorpus besar, menempati ¾ atau lebih dari lebar esophagus; daerahbibir tampak halus, menonjol, dan bagian depannya rata, dengan konturhampir menyatu/bersambung dengan kontur tubuh; ujung ekornyaberbentuk kerucut tajam memanjang dengan ujung meruncing seperti duritumpul. Bentuk tubuh jantan pada dasarnya sama dengan ukuran danbentuk betinanya; ekor agak melengkung kearah 45º - 90º ketika dalamkeadaan relaks dan bentuk ujungnya meruncing seperti duri tumpul; spikulberbentuk duri mawar (“rose-thorne”). Persentase jumlah jantan dalamsatu populasi umumnya banyak berkisar 34,7 – 38,9% dari populasiseluruhnya (jantan dan betina). Karakter-karakter gejala serangan,morfologi nematoda, dan ratio jantan-betina tersebut merupakan karakterspesies Aphelenchoides fragariae (RITZEMA BOS, 1891) CHRISTIE1932. Deteksi adanya spesies nematoda A. fragariae merupakan yangpertama kali dilaporkan di Indonesia, dan sambiloto sebagai inang A.fragariae juga pertama kali dilaporkan baik di Indonesia maupun di dunia.Kata kunci : Sambiloto, Andrographis paniculata, Aphelenchoidesfragariae, identifikasi, nematoda parasitABSTRACTDetermination of parasitic nematode Aphelenchoides sp.causing leaf blotch disease of sambiloto (Andrographispaniculata)Leaf blotch disease by parasitic nematode Aphelenchoides sp. havebeen reported infected and causedleaf drops on sambiloto (Andrographispaniculata (Burm. f.) Wall. ex Nees) (Acanthaceae). Experiments ofspecies determination of the nematode have been carried out inlaboratorium, greenhouse and fields of IMACRI during the year 2005-2006. Identification were done by observing its typical symptoms of theinfected plants caused by the nematode and its nematode morphologicalcharacteristics microscopically on the semi-permanent preparats fixed byTAF (triethanolamine formaldehyde) solution. Typical symptoms of leafblotch were began as chlorotic vein-deliminated areas which later changedto light brown, then dark brown and finally black; or sometimes purplishunder field condition. Microscopically, the female was slender, 0.46 –0.70 mm long and 15 µm width in average, the vulval region cited about2/3 of the body length sized from anterior part; spear slender, 10 µm longwith small and distinct basal knobs; large metacorpus occupying ¾ ormore of the width of the esophagus; lip region almost continuous withbody contour; the tail tip was elongate-conoid ending in a simple bluntspike. The male was abundant and essentially similar to size and shape ofthe female; tail arcuate through 45º to 90 when relaxed, with a simpleblunt terminal spine; spicules rose-thorn shaped. Those describedsymptoms and morphological characters mentioned above were the typicalcharacters of the species Aphelenchoides fragariae (RITZEMA BOS,1891) CHRISTIE 1932. Detection of species A. fragariae was the firstreport in Indonesia; and sambiloto as the natural host of A. fragariae wasthe first report in Indonesia and internationally.Key words: King of bitter, Andrographis paniculata, Aphelenchoidesfragariae, parasitic nematode, identification

Sclerotium sp. merupakan jamur patogen baru pada tanamansambiloto (Andrographis paniculata Ness.) yang dapat mengakibatkankematian. Penyebaran jamur ini masih terbatas di KP Cimanggu, Bogordan KP Cicurug, Sukabumi, Jawa Barat. Tujuan penelitian adalah untukmengetahui pengaruh beberapa faktor lingkungan seperti suhu,kelembaban udara (RH), pH, dan cahaya terhadap pertumbuhan isolatSclerotium sp. asal sambiloto pada media PDA serta kisaran inangnya.Penelitian dilakukan di laboratorium dan rumah kaca Balai PenelitianTanaman Obat dan Aromatik (Balittro), Tahun 2005. Faktor lingkunganyang diuji yaitu suhu ruangan (20, 28, 35 dan 40) o C, kelembaban udara(RH 55, 75, 85, dan 100)%, pH (4, 5, 6, 7, dan 8) dan kondisi cahaya(terang, gelap, dan terang dan gelap selang 12 jam secara bergantian). Ujikisaran inang dilakukan terhadap 3 varietas jagung (ketan, pematung, dansokong) dan 3 varietas kacang tanah (jerapah, kelinci, dan simpai) sertatanaman sambiloto sebagai pembanding. Inokulasi dilakukan dengan caramenempelkan sclerotia jamur di bagian pangkal batang tanaman uji dekatpermukaan tanah. Pengamatan pertumbuhan jamur pada media agar yangdiperlakukan dan pengamatan intensitas serangan penyakit dilakukansetiap hari. Hasil penelitian menunjukkan bahwa isolat Sclerotium sp. asaltanaman sambiloto tumbuh baik pada suhu (20-35) 0 C, RH (55-100)%, danpada kisaran pH 4-8 serta pada kondisi terang atau gelap secara terusmenerus maupun bergantian selang 12 jam. Hasil uji kisaran inangmenunjukkan bahwa Sclerotium sp. dapat menyebabkan kematian tidakhanya pada tanaman sambiloto, tetapi juga pada dua varietas kacang tanah(simpai dan jerapah), sedangkan pada jagung tidak menyebabkan kematian(tahan). Hasil penelitian mengindikasikan bahwa isolat Sclerotium sp.yang berasal dari tanaman sambiloto mempunyai kemampuan bertahanhidup dan berkembang pada kondisi lingkungan yang luas (broadspectrum). Ketidakmampuan jamur tersebut menginfeksi tanaman jagungvarietas ketan, pematung, dan sokong dapat digunanakan sebagai salahsatu cara pengendalian patogen dengan sistem tumpangsari dan rotasi.Kata kunci : Sambiloto, Andrographis paniculata Ness, Sclerotium sp.,karakteristik, fisiologis, Jawa BaratABSTRACTPhysiological Characteristics of Sclerotium sp. Isolatedfrom SambilotoSclerotium sp. is a new destructive fungal patogen on sambiloto(Andrographis paniculata Ness.). The distribution of the patogen was stilllimited in Cicurug, Sukabumi and Cimanggu, Bogor, West Java. The aimof this experiment was to observe the growth of Sclerotium sp fromsambiloto under different environmental factors such as temperature,relative humidity, light condition, and pH on PDA medium as well as itshost range. The experiment was conducted in Indonesian Medicinal andAromatic Crops Research Institute (IMACRI) in 2005. The environmentalfactors tested were temperature (20, 28, 35, and 40) o C; relative humidity(55, 75, 85, and 100)%; pH (4-8); and light condition (continuosly on oroff and 12 hours on and off alternatively). The pathogenicity of theSclerotium sp. was tested against 3 varieties of corn (ketan, pematung, andsokong) and 3 varieties of peanut (jerapah, kelinci, and simpai) as well assambiloto as a comparison. Sclerotia of the fungus were inoculated on thestem base of the plant tested. Observation of the growth of the fungusunder different environmental factors and disease intensity on inoculatedplants was conducted everyday. The results showed that the growth ofSclerotium sp. isolate from sambiloto was affected by differentenvironmental factors. The isolate grew well at (20-35) 0 C, relativehumidity ranged from (55-100)%, pH ranged from 4-8, and lightcondition of both continuosly on or off as well as 12 hours on and offalternativelly. The isolate was pathogenic against sambiloto as well asagainst 2 varieties of peanut (simpai and jerapah), however, it was notpathogenic against all the corn varieties tested. The result indicated thatthe isolate of Sclerotium sp. from sambiloto was a broad spectrum fungalpathogen. The resistency of the corn varieties would be of value forcontrolling the disease through mixed cropping or rotation systems.Key words: Sambiloto, Andrographis paniculata Ness, Sclerotium sp.,physiological characteristics, West Java

Penyakit layu bakteri yang disebabkan oleh Ralstonia solanacearummerupakan kendala utama budidaya jahe, yang menyebabkan kehilanganhasil lebih dari 90%. Upaya pengendalian yang dilakukan belum optimal,karena tidak tersedianya varietas jahe tahan patogen tersebut. Kendalautama untuk memperoleh varietas jahe yang tahan adalah terbatasnyasumber gen ketahanan dan adanya hambatan fisiologis pada prosespersilangan jahe karena sifat inkompatibilitas sendiri, serta rendahnyafertilitas polen menyebabkan persilangan jahe secara konvensional sulitdilakukan. Seleksi in vitro menggunakan medium selektif yangmengandung filtrat patogen merupakan salah satu metode inkonvensionaluntuk meningkatkan ketahanan tanaman. Penelitian ini dilakukan diLaboratorium Kultur Jaringan dan Laboratorium Penyakit Balai PenelitianTanaman Obat dan Aromatik (Balittro) dari bulan April 2008 sa,mpaiOktober 2008 dengan tujuan untuk mengetahui tingkat ketahanan jahepada stadia kalus terhadap filtrat R. solanacearum dan memperolehkonsentrasi filtrat yang tepat sehingga diperoleh varian kalus baru tahanterhadap filtrat patogen tersebut. Kalus embriogenik jahe putih besar asaleksplan meristem berumur 8 minggu, diseleksi selama 3 minggu di dalammedium proliferasi (MS + 3% manitol tanpa zat pengatur tumbuh),mengandung filtrat R. solanacearum. Seleksi bertingkat dilakukan denganmengaplikasikan filtrat R. solanacearum pada konsentrasi berbeda, yaitu:0; 0,1; 0,2; 0,3; 0,4; 0,5; 1; 2; 3; 4; dan 5%, pada tahap pertama. Padaseleksi tahap kedua, kalus disubkultur ke dalam media yang sama dengankonsentrasi filtrat dinaikkan 10 kali dari konsentrasi awal. Penelitianmenggunakan rancangan acak lengkap, diulang 10 kali. Hasil penelitianmemperlihatkan penggunaan filtrat R. solanacearum di dalam mediumkultur in vitro jahe pada seleksi tahap pertama dan kedua menyebabkanterjadinya perubahan warna kalus dari putih kekuningan menjadi kuningkecoklatan dan coklat kehitaman. Berat dan diameter kalus, jumlahembrio globular serta embrio torpedo berkurang secara nyata setelahperlakuan filtrat, pada seleksi tahap pertama maupun kedua seiring denganbertambah tingginya konsentrasi filtrat. Konsentrasi filtrat R.solanacearum yang mampu menginduksi dan menyeleksi kalusembriogenik berkisar antara 0,3 - 2% dari volume medium seleksi kaluspada seleksi tahap 1 dan 3 - 20% pada seleksi tahap 2.Kata kunci : Zingiber officinale Rosc., kalus, seleksi in vitro,ketahanan, filtrat R. solanacearumABSTRACTThe use of R. solanacearum filtrate in callus selection ofin vitro for ginger resistance to bacterial wilt diseaseBacterial wilt disease caused by Ralstonia solanacearum is the mainconstraint in ginger cultivation. It often causes significant yield loss ofmore than 90%. Various controlling techniques are not able to overcomethe disease, due to unavailability of resistant ginger cultivar. Limitation inobtaining resistant ginger variety is caused by several factors includingthe lack of resistant gene, physiological barrier due to the selfincompatibility, and low pollen fertility, these cause difficulty inconventional cross breeding. Therefore, genetic variability enhancementhas to be carried out unconventionally, to obtain ginger variety resistant tothe disease. In vitro selection using a selective medium containing filtrateof the pathogen is one of the potential unconventional method to improveginger plant resistance. The study was conducted at Meristem Culture andPlant Disease Laboratories of IMACRI from April to October 2008 aimingat determining the level of resistant ginger on stage of calli to the filtrateof R. solanacearum and to obtain an appropriate concentration of thefiltrate which induced calli variants resistant to the filtrate. Large whiteginger embryogenic calli meristems of 8 weeks old were selected for 3weeks in proliferation medium (MS + 3% mannitol without growthregulators), containing filtrate of R. solanacearum. For that purpose, twostages of in vitro selection were performed by applying differentconcentrations of R. solanacearum filtrate e.g; 0; 0.1; 0.2; 0.3; 0.4; 0.5; 1;2; 3; 4; and 5% at the first stage selection. Those concentrations were thenmultiplied 10 times at the second stage selection. Experiments werearranged in completely randomized design with 10 replicates. Resultsshowed that the use of R. solanacearum filtrate as selection agent in gingerin vitro culture medium has caused changes in calli color from theyellowish white into the blackish brown. In addition, increase of R.solanacearum filtrate concentration at the 1 st and 2 nd selection stages wasin line with the decreased of the calli weight and diameter, as well asnumber of globular and torpedo embryo. The concentration of R.solanacearum filtrate applied at 0.3 to 2% in the 1 st selection followed by3 to 20% in the 2 nd selection induced resistant embryogenic calli of ginger.Key words : Zingiber officinale Rosc., calli, in vitro selection,resistance, R. solanacearum filtrate

Bacterial wilt caused by Ralstonia solanacearum is one of the mostdestructive diseases on ginger. The aim of this study was to evaluate thepotential use of five different medicinal plants extracts (Acalypha indica,Andrographis paniculata, Centella asiatica, Curcuma xanthorrhiza, andSpinosa oleracea) as sources of plant resistance inducer compounds(elicitor) against bacterial wilt disease on ginger. Salicylic acid was usedas a standard synthetical compound, as well as, water as a controltreatment. The study was conducted at the Indonesian Spice and MedicinalCrops Research Institute, Bogor in 2010-2011. Research was conducted inCompletely Randomized Design that consisted of 7 treatments, 3replicates, and 10 plants/ replicate. Ginger seeds were planted in a mixtureof soil and manure in polybags. One-month old ginger plants were sprayedor drenched with each of the medicinal plant extract before and after R.solanacearum inoculation. This experiment indicated that the medicinalplant extracts tested were effective in reducing wilt disease incidence onginger. Their effectiveness varied depended on the plant species and theapplication method used. Among those five medicinal plant extracts tested,A. indica, A. paniculata, and C. xanthorrhiza were the most stable andeffective. Their effectiveness were comparable with the standardcompound of salicylic acid. This finding indicated that A. indica, A.paniculata, and C. xanthorrhiza were potentially used as sources ofbotanical elicitor compounds. The use of those medicinal plant extracts assources of botanical elicitor, hopefully could increase ginger resistance andrhizome production, as well as reduce the use of synthetic pesticides.Keywords: Medicinal plant extracts, elicitor compounds, inducedresistance, ginger, wilt diseaseABSTRAKLayu bakteri yang disebabkan oleh Ralstonia solanacearummerupakan salah satu penyakit yang merusak tanaman jahe. Penelitian inibertujuan untuk mengevaluasi potensi lima jenis ekstrak tanaman obat(akar kucing, sambiloto, pegagan, temulawak, dan bayam duri) sebagaisumber senyawa penginduksi ketahanan (elisitor) tanaman jahe terhadappenyakit layu. Pada penelitian ini digunakan asam salisilat sebagaisenyawa sintetik standard dan air sebagai perlakuan kontrol. Penelitiandilaksanakan di Balai Penelitian Tanaman Rempah dan Obat, Bogor padatahun 2010-2011. Percobaan dilaksanakan dengan menggunakanrancangan acak lengkap yang terdiri atas 7 perlakuan, 3 ulangan, dan 10tanaman/ ulangan. Rimpang jahe ditanam pada media campuran tanah danpupuk kandang di dalam polibeg. Jahe umur satu bulan disemprot ataudisiram dengan ekstrak tanaman obat sebelum dan setelah diinokulasi R.solanacearum. Hasil penelitian mengindikasikan bahwa ekstrak tanamanobat yang diuji efektif dapat mengurangi kejadian penyakit layu padatanaman jahe. Efektivitas dari tanaman tersebut bervariasi tergantung darispesies tanaman dan cara aplikasinya. Diantara kelima tanaman obat yangdiuji, akar kucing, sambiloto, dan temulawak paling stabil dan efektifdalam mengurangi terjadinya penyakit layu. Efektivitas dari ketigatanaman obat tersebut sama dengan senyawa asam salisilat. Hasilpenelitian menunjukkan bahwa akar kucing, sambiloto, dan temulawakberpotensi untuk digunakan sebagai sumber senyawa elisitor botanis.Penggunaan ekstrak tanaman obat sebagai sumber elisitor botanisdiharapkan dapat meningkatkan ketahanan tanaman dan produksi jaheserta mengurangi penggunaan pestisida sintetik.Kata kunci: Ekstrak tanaman, senyawa elisitor, induksi ketahanan, jahe,penyakit layu.

Nematoda hawar daun (Aphelenchoides fragariae) merupakan salahsatu kendala dalam budidaya tanaman obat sambiloto (Andrographispaniculata). Informasi tentang perilaku dan cara pengendalian nematodapada tanaman sambiloto masih sangat terbatas. Dalam rangka mencari carapengendalian nematoda yang efektif, maka penelitian ini bertujuan untukmengetahui ekobiologi nematoda tersebut seperti kisaran inang, sumberinokulum, dan pestisida. Penelitian dilakukan di laboratorium, rumah kaca,dan kebun percobaan Balittro pada tahun 2006-2008. Studi kisaran inangalami dilakukan dengan mengamati karakteristik gejala khas penyakit,ekstraksi, dan karakterisasi morfologi nematoda dari sampel daun-daungulma yang tumbuh di pembibitan dan pertanaman sambiloto. Studi sum-ber penularan nematoda dilakukan dengan metode bioassay, yaitu denganmengamati gejala hawar daun dan jenis nematoda pada bibit sambilotoyang ditanam pada beberapa macam media tumbuh (tanah steril dicampurdengan beberapa macam jenis bahan organik seperti pupuk kandang,kompos, pupuk organik, dan potongan daun-daun sambiloto sakit).Sedangkan studi sensitivitas nematoda terhadap pestisida sintetik dannabati dilakukan di rumah kaca dan di lapang. Hasil penelitian menun-jukkan bahwa 6 jenis gulma, yaitu babadotan (Ageratum conyzoides),pulus hayam (Acalypha lanceolata), calincing (Oxalys sepium), gulmaBorreria sp., gulma daun sirih (Lindernia sp.), dan paku (Pleocnemia sp.)merupakan inang pengganti nematoda A. fragariae. Bahan organik sepertipupuk kandang dan serasah daun sambiloto sakit dalam tanah merupakansumber penting inokulum A. fragariae, tetapi penyebaran utama penyakitterjadi melalui bibit terinfeksi dan kontak fisik antara daun sakit dengandaun sehat. Perkembangan penyakit hawar daun berlangsung selama 2-4minggu setelah infeksi pertama. Senyawa karbofuran (2-5 g/tanaman),CNSL (cashew nut shell liquid) (0,5-1,0%), tepung (10,0-15,0 g/tanaman),dan ekstrak biji mimba (0,5-1,0%) efektif menekan populasi A. fragariae.Penanaman bibit sehat, sanitasi kebun, penggunaan pupuk kandang yangbenar-benar matang, dan aplikasi pestisida merupakan faktor pentingdalam pengendalian penyakit hawar daun nematoda pada sambiloto.Kata kunci: Andrographis paniculata, sambiloto, nematoda hawar daun,Aphelenchoides fragariae, ekobiologiABSTRACTBioecology of Leaf Blotch Nematode (Aphelenchoidesfragariae) on King of Bitter Plant (Andrographispaniculata)Leaf blotch nematode (Aphelenchoides fragariae) is one of the mostimportant constrains on cultivation of king of bitter plant (Andrographispaniculata). Information on the bioecology and control method of thenematode is still limited. In relation to finding an effective control methodof the nematode, this study aimed to evaluate several bioecological factorsof the nematode, such as its host range, inoculums source, and sensitivityof the nematode to several chemicals. The studies were conducted inlaboratory, green house, and experimental station of the IndonesianMedicinal and Aromatic Crops Research Institute in 2006-2008. Naturalhost range of the nematode was studied by examining the typical diseasesymptoms on leaves of several weeds grown in the nursery and field of theking of bitter plants, followed with extraction and morphologicalexamination of nematodes. Infection source of the nematode was carriedout by bioassay method using healthy king of bitter seedlings grown onsoil planting medium incorporated with suspected infection sources suchas animal manure, compost, organic fertilizer, and diseased leaf cutting ofthe plants. Sensitivity of the nematode to several pesticides (carbofuran,neem seed powder, neem seed extract, and cashew nut shell liquid) wasconducted in the green house and field. The results showed that six weedssuch as Ageratum conyzoides, Acalypha lanceolata, Oxalys sepium,Borreria sp., Lindernia sp., and Pleocnemia sp. grown in the nursery andfield of king of bitter plantation were infected with the nematode; thereforethese plants are natural alternate hosts of A. fragariae. Organic animalmanure and infected fallen leaves of the king of bitter were importantsources of inoculums of A. fragariae, however, main spread of the diseasewas through infected seedlings and direct contact between healthy andinfected leaves. Leaf blotch disease development occurred 2-4 weeks afterfirst infection. Chemicals such as carbofuran (2-5 g/plant), cashew nutshell liquid (0.5-1.0%), neem seed powder (10.0-15.0 g/plant) and extract(0.5-1.0%) were effectively suppressed the nematode. Planting disease-free seedlings, sanitation, and application of well-decomposed animalmanure and certain chemical pesticides are important factors to control theleaf blotch nematode on king of bitter plant.Key words: Andrographis paniculata, king of bitter, leaf blotchnematode, Aphelenchoides fragariae, bioecology.

Pratylenchus brachyurus merupakan salah satu patogen utama padatanaman nilam di Indonesia. Pengendalian yang banyak dilakukan petanisaat ini adalah menggunakan pestisida sintetik. Penggunaan pestisidasintetik yang terus menerus merupakan ancaman terhadap lingkungan, dankesehatan manusia. Bakteri endofit mungkin dapat dimanfaatkan sebagaisalah satu teknik pengendalian nematoda yang ramah lingkungan karenabakteri endofit dapat menghasilkan racun yang toksik terhadap nematoda.Tujuan penelitian adalah melihat pengaruh kultur filtrat bakteri endofitterhadap mortalitas nematoda, penetasan telur dan perkembangannematoda di dalam akar nilam. Penelitian dilakukan di Laboratorium danRumah kaca Hama dan Penyakit Balai Penelitian Tanaman Obat danAromatik Bogor, dari bulan Januari sampai April 2008 menggunakanrancangan acak lengkap (RAL). Filtrat bakteri dibuat dengan caramenumbuhkan bakteri endofit pada media TSB selama 48 jam, kemudiandisentrifugasi dengan kecepatan 7.000 rpm selama 15 menit. Filtratdisaring dengan milipore berdiameter 0,22 µm, selanjutnya filtrat diujipada nematoda in vitro dan rumah kaca. Hasil penelitian menunjukkanbahwa filtrat dapat membunuh nematoda dalam waktu 24 jam dengannilai LC 50 sebesar 7,709%. Bakteri endofit isolat TT2 dan EH11memperlihatkan daya bunuh paling tinggi yaitu 91-100%. Di samping itufiltrat bakteri endofit juga dapat menekan penetasan telur nematoda 48,5-74,6% dibanding dengan kontrol. Namun hanya filtrat bakteri endofitisolat EH11 yang nyata dapat menekan populasi nematoda di dalam akarnilam dengan tingkat penekanan sebesar 81,3%.Kata kunci : Pratylenchus brachyurus, bakteri endofit, kultur filtrat,Pogostemon cablinABSTRACTEffect of culture filtrates endophytic bacteria on themortality, hatching eggs and population of root lesionnematodes Pratylenchus brachyurus on patchouliRoot lesion nematode (Pratylenchus brachyurus) is an importantpathogen of patchouli in Indonesia and causes significant losses. Controlsystem that are done today is using synthetic pesticides. The use ofsynthetic pesticides is a continuing threat to the environment and humanhealth. However, endophytic bacterial culture filtrates may be used as oneof the nematode control that is environmentally friendly. Effect of culturefiltrates endophytic bacteria on the mortality, hatching eggs and populationroot lesion nematodes Pratylenchus brachyurus on patchouli has beendone in vitro and greenhouse. The results showed that the culture filtrate ofendophytic bacteria produced metabolite toxic to nematodes and wereable to kill P. brachyurus 100% within 24 hours with LC 50 7.709%. TT2and EH11 isolates showed high killing power of 91-100%. The culturefiltrates also inhibited hatching of P. brachyurus eggs compared withcontrols. Not all culture filtrates can suppress the nematode population inthe roots of patchouli. EH11 isolates filtrate really pressing nematodepopulations compared to other isolates.Key words: Pratylenchus brachyurus, culture filtrate, endophyticbacteria, Pogostemon cablin

Penggunaan bakteri endofit sebagai agen pengendalian nematodaparasit seperti Meloidogyne incognita pada kapas dan tomat, Globoderasp. pada kentang dan Radopholus similis pada pisang telah banyak ditelitipada beberapa jenis tanaman. Penelitian bertujuan untuk menganalisiskeefektifan beberapa bakteri endofit terhadap perkembangan P.brachyurus, penetrasi, reproduksi, dan kerusakan yang diakibatkannyapada tanaman nilam. Penelitian dilakukan di Laboratorium dan Rumahkaca Hama dan Penyakit Balai Penelitian Tanaman Obat dan AromatikBogor, dari bulan Maret sampai Agustus 2008. Penelitian menggunakanrancangan acak lengkap (RAL) 6 perlakuan dengan 7 ulangan. Lima isolatbakteri endofit, yaitu Achromobacter xylosoxidans TT2, Alcaligenesfaecalis NJ16, Pseudomonas putida EH11, Bacillus cereus MSK, danBacillus subtilis NJ57, diaplikasikan pada setek tanaman nilam denganmetode perendaman akar. Seminggu setelah tanam, nilam diinokulasidengan 500 ekor P. brachyurus. Pengamatan dilakukan terhadap penetrasi,reproduksi, populasi nematoda, dan pertumbuhan nilam. Hasil penelitianmenunjukkan bahwa bakteri endofit A. xylosoxidans TT2, A. faecalisNJ16, P. putida EH11, B. cereus MSK, dan B. subtilis NJ57 dapatmenekan penetrasi dan populasi P. brachyurus ke dalam akar sebesar54,8-70,6% dengan faktor reproduksi (pf/pi) 0,61-0,94 dan meningkatkanpertumbuhan tanaman nilam sebesar 37,86-84,71%.Kata kunci: Pogostemon cablin, bakteri endofit, keefektifan, nematoda,Pratylenchus brachyurus, pengendalian biologiABSTRACTEffectiveness of endophytic bacteria to controlPratylenchus brachyurus nematode on patchouliThe use of endophytic bacteria as biocontrol agents for nematodes,such as Meloidogyne incognita on cotton and tomatoes, Globodera sp. onpotatoes and Radopholus similis on bananas has been widely studied inseveral crops. The aim of the study was to investigate the effectiveness ofsome endophytic bacteria to control P. brachyurus, penetration,reproduction, and plant fresh weight production. Five isolates, namely A.xylosoxidans TT2, A. faecalis NJ16, P. putida EH11, B. cereus MSK, andB. subtilis NJ57 were applied to the patchouli cutting roots by soakingmethod before planting. A week after planting, the plants were inoculatedwith 500 juveniles and adults of P. brachyurus. Observations were doneon penetration and reproduction rates of the nematode, and growth ofpatchouli plant. Under greenhouse condition, A. xylosoxidans TT2, A.faecalis NJ16, P. putida EH11, B. cereus MSK, and B. subtilis NJ57reduced penetration rate of P. brachyurus into the patchouli roots by 54.8to 70.6% and suppressed nematode population with pf/pi value 0.61 to0.94. Growth of inoculated plants increased by 37.86 to 84.71% comparedwith uninoculated (control) ones.Key words: Pogostemon cablin, endophytic bacteria, effectivenessnematode, Pratylenchus brachyurus, biological control