Judul: Eksplorasi dan Identifikasi Bakteri Agens Hayati dari Permukaan Tubuh Lundi (Coleoptera: Scarabaeidae)
Abstrak: Pengendalian hayati merupakan teknik pengendalian organisme pengganggu tanaman yang ramah lingkungan. Penelitian ini bertujuan mengeksplorasi dan mengidentifikasi bakteri agens hayati yang berasal dari permukaan tubuh lundi (Coleoptera: Scarabaeidae). Penelitian ini dilakukan di Laboratorium Bakteriologi Tumbuhan, Departemen Proteksi Tanaman IPB dari bulan Maret hingga September 2015. Isolat bakteri yang diperoleh dari hasil isolasi adalah sebanyak 15 isolat asal Jonggol dan 11 isolat asal Cikabayan. Isolat tersebut terdiri atas 13 bakteri Gram negatif dan 13 bakteri Gram positif. Satu dari 26 isolat bakteri, LC06, merupakan patogen pada tanaman sedangkan isolat lainnya bukan patogen pada tanaman. Hasil uji antagonisme menunjukkan bahwa terdapat 14 isolat bakteri memiliki reaksi antagonis terhadap Helminthosporium oryzae, 20 isolat terhadap Pyricularia oryzae, delapan isolat terhadap Rhizoctonia solani, dan dua isolat terhadap Xanthomonas oryzae pv. oryzae. Isolat bakteri LJ10 dan LJ13 memiliki persentase penghambatan tertinggi dibandingkan dengan isolat lainnya. Isolat LJ10 memiliki persentase penghambatan sebesar 26.6% terhadap H. oryzae, 30.3% terhadap P. oryzae dan 52.2% terhadap R. solani. Isolat LJ13 memiliki persentase penghambatan sebesar 28.5% terhadap H. oryzae dan P. oryzae, 34.5% terhadap R. solani, dan juga 53.3% terhadap X. oryzae pv. oryzae. Hasil identifikasi tersebut menunjukkan bahwa isolat LJ10 memiliki kemiripan sekitar 97% sampai 98% dengan bakteri Citrobacter farmeri, sedangkan isolat LJ13 memiliki kemiripan sebesar 97% dengan bakteri Bacillus sp..
Keyword: agens hayati, lundi, patogen penting pada padi

Judul: Bakteri Pada Termitarium Macrotermes Gilvus Hagen. (Blattodea: Termitidae) Dan Uji Potensinya Sebagai Agens Hayati Penyakit Penting Padi
Abstrak: Mikroorganisme agens hayati diduga memiliki potensi untuk mengendalikan penyakit penting tanaman. Mikroorganisme tersebut dapat ditemukan pada berbagai habitat seperti termitarium. Penelitian ini bertujuan mengisolasi, menyeleksi, dan mengidentifikasi bakteri pada termitarium M. gilvus yang berpotensi sebagai agens hayati. Isolasi dilakukan dengan metode pengenceran berseri kemudian disebarkan pada media agar. Penapisan isolat bakteri meliputi uji hipersensitif dan uji antagonis terhadap H. oryzae, P. oryzae serta X. oryzae pv. oryzae. Identifikasi bakteri dengan perunutan nukleotida penyandi gen 16S rRNA. Isolat bakteri dari termitarium yang berhasil diperoleh adalah sebanyak 29 isolat, namun hanya 22 isolat yang diuji potensi antagonisnya. Isolat WYTS1 dan NATS2 adalah isolat yang paling berpotensi sebagai agens hayati. WYTS1 dapat menghambat P. oryzae rata-rata 21.48%, sedangkan isolat NATS2 dapat menghambat H. oryzae, P. oryzae, dan X. oryzae pv. oryzae rata-rata 57.14%, 62.22%, dan 15.60%. Hasil analisis homologi urutan nukleotida gen 16S rRNA kedua isolat tersebut dengan data yang terdapat di GenBank masing-masing menunjukkan kemiripan dengan Leifsonia sp. sebesar 80% dan Brevibacillus antara 80-81%.
Keyword: Brevibacillus, kelapa sawit, Leifsonia, Pyricularia oryzae, Xanthomonas oryzae pv, oryzae

Judul: The Effects of Variance of Interest rate to Variance of Annuity Future Values
Abstrak: Time value of money is a concept that refers to the difference of the value of money due to time difference. The value of money for present time would not be the same as the value of money in the future. The value of money for present time is called as Present Value (PV) of the money and the value of money for future time is called Future Value (FV) of the money. Determination the value of money, for present and future time, depends on the time and rate of return. The value of money is determined by several factors such as inflation, fluctuation of interest rates, and government policy in securities and taxation. Due to fluctuation of the value of money we need a FV formulation, it is useful for knowing whether an investment can be profitable or not, and this information is useful also in budget analysis. Annuity is defined as a series of payments made for a specific period. The payment, fixed or varied, can be made at the beginning or at the end of the period. Annuity paid at the beginning of the period is called annuity-due and annuity paid at the end of the period is called immediate annuity-certain. The accumulated value of the annuity after few years later is called as a final value or a future value. Burnecki et al. (2003) have discussed about the FV of a fixed-rate annuity in which payments are made according to the arithmetic or geometric series. They have also examined FV for annuities in which payments are made according to arithmetic or geometric series with random rates of interest. This paper examines FV for annuity-due in which payments are made according to arithmetic or geometric series with interest rates as a random variable, which is normal distribution ,  . Future value formula is expressed in recursive form. FV for annuity-due which payments are made according to the arithmetic or geometric series with random rates of interest is calculated by theoretical way and simulation way. The random rates of interest is denoted as k k i  i  , where k i an independent random variable; i is a constant and k  is a random variable which has normal distribution ,  . By using the determined parameters, a sequence of random rates of interest are generated for theoretical calculation. Meanwhile for the simulation, the random rates of interest is generated 1000 times for the simulation. The generated data give mean value, variance, and standard deviation. Moreover, error of mean value, variance, and standard deviation from the theoretical and simulation results are calculated. Error calculation uses Symmetric Mean Absolute Percentage Error (SMAPE). The smaller the value of SMAPE is the more accurate the simulation. The interest rate variances are varied from 0.000036 to 0.0001 to study the relationship between variance of rates of interest and variance of future value. The theoretical and simulation results show that when the variance of random rates of interest increases, then the variance of FV increases linearly. FV of the annuity-due in
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