Judul: Evaluasi Keefektifan Penghambatan Beberapa Agens Biokontrol terhadap Pertumbuhan Marasmius palmivorus Sharples
Abstrak: Marasmius palmivorus Sharples is a cause of bunch rot disease on oil palm trees. A study has been conducted to evaluate the effectiveness of some biocontrol agents in inhibiting the growth of M. palmivorus. Antagonistict test between M. palmivorus and biocontrol agents was conducted by using dual culture method (Trichoderma harzianum (TH17), Gliocladium fimbriatum (G84), Bacillus subtilis (B12), Pseudomonas fluorescens (P1), actinomycetes APS5 and APS12) and poisoning test (using metabolit extract of APS5 and APS12) in potato dextrose agar. Variable measured for dual culture method and poisoning test was percentage of inhibition. The result showed actinomycetes (APS5 and APS12) metabolit could 100% inhibit the growth of M. palmivorus at 1 even up to 6 days after incubation periods. Meanwhile, by dual culture method, APS12 and APS5 isolates could not inhibit the growth of pathogenic colonies. Antagonistic fungus TH17 and G84 have effectively inhibited 100% M. palmivorus growth at 4 days after incubation. The inhibition ability of TH17 and G84 significantly higher than B12 isolate. B12 isolate was only able to inhibit 36.88% growth of pathogens at 6 days after incubation. P1 isolate was not able to inhibit M. palmivorus growth until 6 days after incubation (inhibition percentage -33.01%).
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Judul: Pengujian Bacillus thuringiensis galur SAHA 12.08 sebagai pengendali pertumbuhan cendawan penyebab bercak daun kelapa sawit
Abstrak: Oil palm (Elaeis guineensis Jacq.) is one of major agriculture commodities in Indonesia. The disease caused by pathogenic fungi such as Curvularia affinis and Colletotrichum gloeosporoides could inhibit the growth of oil palm seedling plants. Cell wall, mycelia cells, stalks, and conidium of fungi that composed by chitin, can be degraded by chitinolytic bacteria through its ability to produce the chitinase enzyme. This research was aimed to study the ability of Bacillus thuringiensis strain SAHA 12.08 in inhibiting C. affinis and C. gloeosporoides that attacked oil palm leaf through in vitro experiment. Bacillus thuringiensis strain SAHA 12.08 showed inhibitor activity to pathogenic fungi using 24 hour and 12 hour bacteria culture. Result of inhibition test using Detached-Leaf Assays method showed that capability of Bacillus thuringiensis as biocontrol activity against C. affinis was 85% and 90%, and against C. gloeosporoides was 96% and 59%. Inhibition of the strain against C. affinis and C. gloeosporoides using in vitro test were 27,8% and 28,2 % respectively. Bacillus thuringiensis strain SAHA 12.08 had antagonistic activity at in vitro test using leaf of oil palm and showed biocontrol activity against C. affinis and C. gloeosporoides
Keyword: Bogor Agricultural University (IPB), oil palm, C. gloeosporoides, C. affinis, Chitinolytic bacteria

Judul: Orbit elektron dan probabilitas level energi sistem chaotic atom hidrogen
Abstrak: a. Mendapatkan orbit elektron sistem chaotic atom hidrogen (dalam koordinat semiparabolik). b. Mendapatkan probabilitas dua level energi yang berdekatan dari sistem chaotic atom hidrogen.
Keyword: Atom, Orbit Elektron