Judul: Potensi Pemangsaan Cryptolaemus Montrouzieri (Coleoptera: Coccinellidae) pada Kutu Putih Singkong Phenacoccus Manihoti (Hemiptera: Pseudococcidae).
Abstrak: Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), merupakan hama pendatang baru yang menyebabkan kerusakan berat pada pertanaman singkong di Indonesia. Salah satu musuh alami yang ditemukan dapat memangsa kutu putih adalah kumbang predator Cryptolaemus montrouzieri (Mulsant) (Coleoptera: Coccinellidae). Pengamatan dilakukan dengan melihat potensi pemangsaan dari berbagai stadia larva C. montrouzieri pada berbagai instar kutu putih Phenacoccus manihoti pada kondisi laboratorium. Tingkat pemangsaan terpengaruh oleh masa hidup predator. Nilai pemangsaan tertinggi yaitu oleh larva predator instar-3 diikuti oleh instar-2, instar-1 dan yang terendah yaitu instar-4. Nimfa kutu putih yang paling banyak dimangsa oleh satu ekor larva predator yaitu nimfa kutu putih instar-1 dan instar-2, dengan rata-rata 461.5 dan 425.6 individu, instar-3 rata-rata sebanyak 163.7 individu dan imago hanya 36.5 individu.
Keyword: Cryptolaemus montrouzieri, kutu putih singkong, Phenacoccus manihoti, predator

Judul: Biologi, Neraca Hayati dan Pemangsaan Cryptolaemus montrouzieri (Mulsant) (Coleoptera : Coccinellidae) pada Paracoccus marginatus Williams & Granara de Willink (Hemiptera : Pseudococcidae).
Abstrak: Kutu putih pepaya, Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae), adalah hama invasif yang bersifat polifag yang terdeteksi untuk pertama kalinya di Indonesia pada tahun 2008. Salah satu musuh alami yang sering ditemukan di lapangan adalah kumbang predator Cryptolaemus montrouzieri (Mulsant) (Coleoptera : Coccinellidae). Penelitian dilakukan di laboratorium dengan tujuan untuk menentukan parameter biologi dan neraca hayati, serta kapasitas dan preferensi pemangsaan C. montrouzieri pada P. marginatus. Pengujian biologi dan neraca hayati dilakukan pada 100 butir telur, pengamatan dilakukan terhadap masa penetasan, pergantian kulit, pupasi, nisbah kelamin, serta kematian yang terjadi pada setiap stadia. Imago yang muncul kemudian dipasangkan lalu dihitung keperidian dari setiap imago betina. Pengujian laju pemangsaan dilakukan dengan memberikan predator mangsa 200 telur dan berbagai nimfa instar kutu putih masing-msing 60 ekor yang semuanya dicampur dalam satu cawan. Uji preferensi pemangsaan dilakukan dengan memberikan predator mangsa 100 telur dan berbagai nimfa instar kutu putih masing-masing 30 ekor, semuanya dipisah dalam cawan yang berbeda. Pengamatan dilakukan setelah 24 jam terhadap jumlah kutu putih yang dimangsa. Hasil penelitian menunjukkan bahwa telur C. montrouzieri menetas dalam 4.35 hari. Perkembangan larva instar-1 4.23 hari, instar-2 4.21 hari, instar-3 5.84 hari, instar-4 5.93 hari. Prapupa berlangsung 1.95 hari dan pupa 7.55 hari. Total masa perkembangan pradewasa bakal jantan adalah 33.97 hari dan bakal betina 34.1 hari. Masa hidup imago jantan adalah 51.34 hari, sedangkan betina 83.39 hari. Jumlah telur yang diletakkan oleh seekor betina rata-rata 198.49 butir. Studi neraca hayati menunjukkan nilai laju reproduksi bersih (Ro) 117.11 individu/betina/generasi, laju pertambahan intrinsik (rm) 0.073 individu/betina/hari, rataan masa generasi (T) 64.776 hari, masa penggandaan (DT) 9.426 hari, dan laju pertambahan terbatas (λ) adalah 1.076 per hari. C. montrouzieri menunjukkan laju pemangsaan yang tinggi, dengan larva instar-4 merupakan fase paling rakus. Jumlah telur, nimfa instar-1, instar-2, instar-3 dan imago betina kutu putih yang dimangsa per hari oleh larva instar-4 predator masing-masing adalah 188.0 butir, 53.4, 44.0, 26.8 dan 15.6 ekor. Indeks preferensi Manly menunjukkan bahwa larva dan imago C. montrouzieri lebih memilih telur dan nimfa instar-1 P. marginatus dibandingkan nimfa instar-2 dan instar-3 atau imago betina.
Keyword: predator, kutu putih, Cryptolaemus montrouzieri, Paracoccus marginatus

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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