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Abstrak :
The objective of this research was to determine the pathogenicity of Nomuraea rileyi on larvae of Spodoptera litura. The isolate was from the infected Crocidolomia binotalis. This fungus was reproduced in rice, corn, and mixture of rice and bran media. The results showed that rice was the best medium for N. rileyi. The spore production in the media of rice, corn, and mixture of rice and bran media after three weeks cultivation age were 7,65 x 10"; 1, 78 x 1013; and 1,06 x 1013 spore-/ml, respectively. The pathogenicity tests of N. rileyi were employed against three instars (first, third, and fifth instar) of S. litura by spraying the soybean leaves with different concentration of spores. The spray volume was calculated based on the recommended field rate (500 I/ha). No mortality was observed on the first instar of S. litur. However, the third and fifth instar were found to be more susceptible to N. rileyi than the first instar with the LC50 values of 1,471 x 10° and 1,754 x 106 spore/ml respectively. Furthermore the LC95 of N. rileyi against the third and fifth instar was 1,319 x 10" and 2,574 x 1017 spore/ respectively.

Abstrak :
Spodoptera litura (Fab.) Atau ulat grayak adalah salah satu jenis hama polifagik yang sangat merugikan bagi pertumbuhan tanaman budidaya. Pemanfaatan ekstrak tanaman adalah salah satu alternatif efektif dalam mengendalikan hama ulat grayak saat ini. Dendrophthoe pentandra (L.) Miq. termasuk parasit yang mengandung metabolit sekunder dengan berbagai bioaktif, seperti antidiabetik, antioksidan, antikanker, hipertensi, dan sifat antibakteri. Namun, bioaktivitas parasit D. pentandra di pertanian, seperti antifeedant terhadap hama serangga, belum diketahui potensinya. Oleh karena itu, penelitian ini bertujuan untuk mengetahui aktivitas antifeedant parasit D. pentandra pada larva S. litura. Subjek penelitian ini adalah ekstrak kasar batang D. pentandra dan parasit daun dengan konsentrasi 500, 1000, 1500, 2000, dan 2500 ppm. Sebanyak 20 larva neonatal S. litura di setiap ulangan diberi pakan buatan yang mengandung kedua ekstrak. Menguji aktivitas antifeedant menggunakan uji makan kronis selama 7 hari. Pengambilan data uji antifeedant meliputi rata-rata persentase penurunan aktivitas makan, rata-rata berat badan larva S. litura, dan rata-rata jumlah larva S. litura mati. Hasil penelitian menunjukkan bahwa kedua ekstrak tersebut berpotensi sebagai antifeedant terhadap larva S. litura. Konsentrasi efektif D. pentandra ekstrak batang dan daun dalam mengurangi aktivitas makan larva S. litura, yaitu pada konsentrasi 1500 dan 2500 ppm.

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Spodoptera litura (Fab.) Or armyworm is one type of polyphagic pest that is very detrimental to the growth of cultivated plants. Utilization of plant extracts is one effective alternative in controlling armyworm pests today. Dendrophthoe pentandra (L.) Miq. including parasites which contain secondary metabolites with various bioactives, such as antidiabetic, antioxidant, anticancer, hypertension, and antibacterial properties. However, the bioactivity of parasites of D. pentandra in agriculture, such as antifeedants against insect pests, is not yet known for its potential. Therefore, this study aims to determine the antifeedant activity of D. pentandra parasites on S. litura larvae. The subjects of this study were crude extracts of D. pentandra stem and leaf parasites with concentrations consisting of 500, 1000, 1500, 2000, and 2500 ppm. A total of 20 S. litura neonatal larvae in each replicate were given artificial feed containing both extracts. Testing antifeedant activity using chronic feeding assay for 7 days. The retrieval of antifeedant test data included the average percentage decrease in feeding activity, the average body weight of S. litura larvae, and the average number of dead S. litura larvae. The results showed that both extracts have potential as antifeedants against S. litura larvae. Effective concentrations of D. pentandra stem and leaf parasite extracts in reducing the feeding activity of S. litura larvae, namely at concentrations of 1500 and 2500 ppm

Abstrak :
Indonesia needs approximately 2.20 tons of soybean per year. The domestic production only meets 35-40% of the demand and the remaining 60-65% are imported from foreign countries....

Abstrak :
Sanjaya, Machmudin D, Kurniawati ND. 2010. Histological study of SlNPV infection on body weight and peritrophic membrane damage of Spodoptera litura larvae. Nusantara Bioscience 2: 135-140. The effect of SlNPV infection on body weight and peritrophic membrane damage of Spodoptera litura Fab. larvae has been carried out. The method was used Probit analysis, and based on LD 50 the virus was infected to know body weight and post infection damage.The damage of histological structure caused by SlNPV (0, 315, 390, 465, 540 dan 615 PIB/mL) was investigated after 0, 12, 24, 72 and 96 hours post infection. The histological material was prepared by using parafin method after fixation with Bouin Solution, then slice into 7 um and colored with Hematoxilin-Eosin. The result showed that the exposure SlNPV cause decreasing food consumption especially on 540 PIB/mL give average rate as amount of 0.1675 mg. The descriptive obsevation on structural intact of peritrophic membrane histology caused by SlNPV infection shows a tendency to decrease, while in control, there was no damage at all. The longer the exposition of virion in the midgut lumen the more damage on peritrophic membrane occurred. The severest damage occurred 96 hour after infection. The result prove that haNPV virion can destroy hystological structure of midgut

Abstrak :
Spodoptera litura is one of the major pests on red chili peppers (Capsicum annuum). Larvae damage crops by biting, chewing, and then eating the lower surface of the leaves. The leaves became transparent white, and severe damage only leaves the leaf’s midrib and veins. Papaya latex (Carica papaya) could be used as a pesticide because it contains cysteine protease, which is a substance that can inhibit the insects from eating the leaves or even kill the pests. The purpose of this study was to produce an organic pesticide from the cysteine protease extracted from papaya latex that is effective against Spodoptera litura. A completely randomized design was used with latex from papaya leaves, papaya rind, and papaya fruit. The methods used were blending and tapping. The blending method was conducted via a chemical extraction using buffer phosphate and ammonium sulfate. The tapping method was conducted via a chemical extraction using acetone. These methods were compared by using an enzyme activity test and efficacy test. The enzyme activity test used a UV-Vis spectrophotometer and the efficacy test was done on Spodoptera litura larvae, which were given red chili pepper leaf covered with an organic pesticide from cysteine protease.

Abstrak :
Senyawa trifeniltimah asetat termasuk golongan trifeniltimah karboksilat tidak hanya memiliki kegunaan sebagai antifeedant namun juga bersifat toksik, sehingga memiliki kemampuan untuk mempengaruhi indera perasa serangga yang akan menurunkan keinginannya untuk makan dan sifat toksiknya memiliki efek mematikan pada konsentrasi terendah yaitu 30 ppm. Sintesis trifeniltimah asetat ini dilakukan dengan menggunakan material awal trifeniltimah klorida dalam pelarut aseton dan dengan penambahan natrium asetat berlebih. Produk yang dihasilkan berupa kristal berwarna putih kekuningan sebanyak 0,5864 gram (hasil 57,4 %). Karakterisasi senyawa yang dihasilkan dilakukan dengan menggunakan uji titk leleh sebagai uji awal dengan nilai kisaran titik leleh yang terbaik yaitu 119 -122 °C yang didapatkan pada waktu refluks 3 jam. Pada serapan daerah inframerah menunjukkan hasil yang mendekati dengan standar saat produk direfluks selama 3 jam yaitu dengan terdapatnya serapan pada 500 – 600 cm-1 yang merupakan daerah serapan Sn-O. Identifikasi dengan kromatografi gas (GC) yang menghasilkan satu puncak yaitu pada Rt 15,25 dan dengan detektor spektrometri massa (MS) diperoleh fragmentasi dari produk sebagai berikut: Ph3Sn Ph2Sn PhSn Sn m/z 350 m/z 273 m/z 196 m/z 119 Ph C4H3+ m/z 77 m/z 51 Kemudian senyawa trifeniltimah asetat diuji efektivitasnya sebagai antifeedant dan sifat toksiknya terhadap ulat grayak Spodoptera litura dengan metode celup daun. Hasilnya menunjukkan bahwa seiring dengan meningkatnya konsentrasi, nilai antifeedant factor (AF) juga makin meningkat yang menunjukkan berkurangnya aktivitas makan. Hal ini dibuktikan melalui uji dengan pilihan choice test. Selain itu dengan meningkatnya konsentrasi, ulat juga makin banyak yang mati. Hal ini menunjukkan bahwa senyawa trifeniltimah asetat bersifat toksik dengan menggunakan metode tanpa pilihan (no choice test).