Judul: Pengaruh Formulasi Kasar dan Halus untuk Pembiakan Streptomyces katrae terhadap Penghambatan Populasi Xanthomonas oryzae pv. oryzae serta Daya Tumbuh Benih Padi
Abstrak: Streptomyces katrae is bacteria that included in the actinomycetes. The ability of actinomycetes is producing antibiotics that can suppress the development of disease in plants. Growing S. katrae using organic wastes often to minimize production costs. The objective of this study is to get an effective formulation for growing S. katrae to Xanhomonas oryzae pv. oryzae and rice seed growth. S. katrae cultured in 8 formulations, rice + rough waste of mushroom baglog (B1L1); rice + smooth waste of mushroom baglog (B1L2); rice flour + rough waste of mushroom baglog (B2L1); rice flour + smooth waste of mushroom baglog (B2L2); corn + rough waste of mushroom baglog (J1L1); corn + smooth waste of mushroom baglog (J1L2); cornmeal + rough waste of mushroom baglog (J2L1); cornmeal + smooth waste of mushroom baglog (J2L2). Results showed a population S. katrae was highest in the treatment of B1L1 is 102.83x104 cfu/ml and B1L2 is 46.58x104 cfu/ml. This is because the nutrients found in the rice helps the grow of bacteria compared with corn. Rice seed treated with a seed coating B1L1 and B1L2 formulation also has a high shoots better than the control treatment. Germination with seed coating treatment B1L1 and B1L2 percentage of 90% and amounted to 93.3%. Provision of actinomycetes in rice seed can also suppress populations of Xanthomonas oryzae pv. oryzae causes kresek disease.
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Judul: Formulasi Aktinomiset Menggunakan Beberapa Jenis Tanah sebagai Agens Hayati Penyakit Kresek (Xanthomonas oryzae pv. oryzae) pada Padi
Abstrak: Biological control is one of the techniques for controlling plant diseases using antagonistic microorganisms. Actinomycetes are bacteria that have high potential as biological agents to control plant pathogens. Actinomycetes could be formulated with a wide range of carrier in the form of flour or powder. Soil could be used as a carrier materials in a formulation because soil has a mineral content that could promote plant growth. The purpose of this research was to determine the effectiveness of actinomycetes’s formulation that used three types of soil (latosol, andosol, and podzolic) to suppress Xanthomonas oryzae pv. oryzae (Xoo). Tests that conducted in this research include antibiosis test of actinomycetes against Xoo, antibacterial formulation test of actinomycetes against Xoo, and test the effectiveness of the formulation to suppress leaf blight disease and for the growth of rice seedlings. The result of antibiosis test indicated that antibiosis of actinomycetes could suppress the growth of Xoo by means of in vitro. The result of antibacterial formulation test showed that there is a relationship between the types of formulations with concentration level. Formulation actinomycetes using andosol soil could suppress population of Xoo by 27.25%. Population of Xoo also could be suppressed by formulation actinomycetes using podzolic soil by 25.62% and formulation actinomycetes using latosol soil by 14.24%. Formulation actinomycetes using andosol soil not only could suppress population of Xoo but also could induce plant growth by increasing the average length of roots and plant height compared with the control.
Keyword: podsolic., andosol, latosol, antagonistic microorganism, rice disease

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular