Judul: Beberapa aspek biologi parasitoid Aphidius sp. (Hymenoptera :Aphidiidae) pada berbagai instar inang Myzus persicae Sulzer (Homoptera : Aphididae) pada tanaman kentang (Solanum tuberosum L.)
Abstrak: Penelitian ini dilakukan di Laboratorium Ekologi dan taksonomi Serangga, jurusan Hama dan Penyakit Tumbuhan, Fakultas Pertanian, Institut Pertanian Bogor, sejak bulan Desember 1989 sampai dengan bulan Mei 1990. Penelitian bertujuan untuk mengetahui siklus hidup dan keperidian M. persicae Sulz. pada tanaman kentang dan siklus hidup serta perkembangan parasitoid Aphidius sp. pada berbagai instar inang M. persicae pada tanaman kentang.... Hasil penelitian menunjukkan bahwa siklus hidup M. per- sicae pada tanaman kentang di Bogor berkisar dari 6-8 hari. Rata-rata stadium nimfa instar I, II, III, dan IV adalah 1.3 hari, 1.2 hari, 1.2 hari, dan 1.6 hari. Rata-rata masa prakelahiran 1.0 hari. Lama hidup imago rata-rata 10.4 hari dengan rata-rata jumlah keturunan selama hidupnya adalah 32.4 nimfa. Masa perkembangan parasitoid sejak telur dile- takkan sampai menjadi mumi membutuhkan waktu rata-rata 9.67-10.0 hari pada nimfa instar II, 7.0-7.45 hari pada nimfa instar III, dan 5.0-5.25 hari pada nimfa instar IV. Masa perkembangan parasitoid sejak menjadi mumi sampai perasitoid muncul membutuhkan waktu rata-rata 3.29-3.40
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Judul: Host Plants, Pamitoids and Hyperparasitoids of Green Peach Aphid, Myzus persicae (Sulzer) (Hornoptem: Aphididae) in the neighburhood of Bogor and Cimjur (West Java)., Tumbuhan inang, parasitoid dan hiperparasitoid kutudaun Myzus persicae (Sulzer) (Homoptera: Aphididae) di sekitar Bogor dan Cianjur, Jawa Barat
Abstrak: The green peach aphid Wtls persicae (Sulzer) is truly a cosmopolitan species, very poIyphagous, reproduces parthenogenetically in the tropics, and has a short life cycle. It is a common pest of many cultivated piants and act as vectors of many plant viruses. The predators, parasitoids and pathogens are the important natural enemies of green peach aphid and other aphids. In general this r e m h investigates the natural host plants, parasitoids, and hyperparasitoids of green peach aphid in the neighbourhood of Bogor and Cianjur (West Java). The special purpose of this resarch is to study the diversity of the host plants, the parasitoids, and hyperparasitoids of the aphid and their vertical distributions in the areas. Besides, the influence of the diversity of host crop plants and the application of insecticide on the aphid parasitoids and hrperparasitoids were also studied. Labot~torye xperiments were conducted to investigate the potential of parasitoids as agent of biological control. The results showed that the aphids' host plant diversity is high, and that plant species which are taxonomically related are potential hosts of the aphld. Dominant host plants belong to families Solanaceae and Brassicaceae. There were six species of parasitoids attacking the aphid, i,e. : Aphidius rosae Halida y, Aphidius delicat ers Baker, Aphiditrs sp., Diaeretiella rape (M' intosh) (Aphidiidae), Aphelinus asychis (Walker), and Apkelinus sp. (Aphelinidae). Four species of hyperpamitoids found attacking those parasitoids, i-e.: Aphtdencyrtus sp., Coagerus sp., Ooemyrtus sp. (Emyrtidae), and Charips sp. (Chanpidae). Population abundance and d~stributiono f the parasitoids of the aphid were influenced by the crops plant species, population density and distribution of the aphid, season, and application of insecticide. The species vertical distribution of the aphids' parasitoids and h yperparasi toids differ and apparently are influenced by the occurrence of the aphids' host plant and elevation above sea level. Laboratory experiment showed that the parasitoids D. rape, could suppressed the aphids' population to 62,7%, and the other pamitoid, Aphelinm sp. to 59,4%. The last mentioned parasitoids killed its host by host feeding, besides parasitization. The use of those parasitoids in applied biological control programs is recommended, however more researches are still needed, especially in aspects of field biaecology, mass rearing and release technologies., Kutudaun Myzus persicae (Sulzer) merupakan species yang kosmopolit, polifag, di daerah tropis berkembangbiak partogenetik dan siklus hidupnya pendek serta dapat berperan sebagai hama dan vektor penyakit virus tanaman. Predator, parasitoid dan patogen merupakan musuh alami penting kutudaun.
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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