Judul: Biological Control of Helopeltis sp., the Major Pest of Acacia crassicarpa Tree Plantation with Entomopathogenic Fungi Beauveria bassiana and Lecanicillium lecanii
Abstrak: Helopeltis sp. have been known as one of major pests on tea, cacao and cashew plantation. Recently, Helopeltis sp. have been also reported attack Acacia crassicarpa plantation in Sumatra and Kalimantan. For such extensive plantation, low cost biocontrol agents such as entomopathogenic fungi are choosen because of the simplicity for mass production. The information about biology of Helopeltis sp. in agricultural commodities especially tea plantation is quite common. However, it is very few reported in forest plantation. The research will contribute the data on biology of Helopeltis sp. in acacia plantation. The objective of this study was also to measure the effectiveness of Beauveria bassiana and Lecanicillium lecanii as biocontrol agent against Helopeltis sp. Both fungi that were used in this study were obtained from IPB Insect Pathology Laboratory. The tested insect, Helopeltis sp. was collected from Gunung Mas tea plantation and kakao plantation, University Farm IPB Sukamantri. The insects were reared in laboratory. Fifteen pairs of adult Helopeltis sp. were placed in fifteen plastic cages (Ф 20 cm, h 35 cm) with young acacia plant. Praoviposition, oviposition, and each stadia period were observed every day until the insect died. Three hosts of Helopeltis sp.; tea shoot, acacia shoot, and cacao pod,were placed in plastic container (Ф 35 cm, h 25 cm). Preference host test was observed during 5 hours after introduction of the nymph into container. Insect preference for egg laying was observed during 3 days after one pair of adult Helopeltis sp. have been entered. Four levels of conidial density, 109, 108, 107, 106 conidia/ mL were applied to adult Helopeltis sp. (B. bassiana) and 3rd instar nymph (L. lecanii). Daily mortality was observed until seven days post treatment. The result showed that female Helopeltis sp. produced 13-23 eggs after mating, egg stadia was 9 days, 1st – 5th instar nymph were 2, 3, 4, 3, 3 days.The adult stadia was approximately 15 days. Helopeltis sp. prefered to attend tea shoot (20%) greater than cacao pod (14%) and acacia shoot (10.33%). Helopeltis sp. prefered to lay eggs in cacao pod (133 eggs), rather than tea shoot (91 eggs) and acacia shoot (30 eggs). B. bassiana at 106 conidia/ mL density caused 81.25% mortality of adult Helopeltis sp., while 100% mortality at five days observation could be attained by using 108 conidia/ mL. The LC50 of B. bassiana was 3.2 x 104 conidia/ mL, at four days observation and LT50 was 4.214 days at 106 conidia/ mL. On the other hand, L. lecanii at 106 conidia/ mL caused 96.25% mortality of 3rd instar nymph of Helopeltis sp. at six days observation with the LC50 value at two days observation was 1.03 x 106 conidia/ mL, LT50 was 1.198 days and LT95 was 5.25 days. The results of these study showed that two fungi were effective against Helopeltis sp. in this bio assay.
Keyword: Beauveria bassiana, biology, conidia, density, Helopeltis sp.,, Lecanicillium lecanii, mortality, preference

Judul: The Effectiveness of Entomopathogenic Fungi, Beauveria bassiana (Balsamo) Vuillemin and Lecanicillium lecanii (Zimm.) (Viegas) Zare & Gams Against The Asiatic Corn Borer, Ostrinia furnacalis Guenée (Lepidoptera: Crambidae).
Abstrak: This study was conducted at the Insect Pathology Laboratory, Plant Protection Department, Bogor Agricultural University, from March to September 2013. Tested insects,Ostrinia furnacalis, were collected from farmers cornfield in Dramaga, Bogor andthen reared in the laboratory. Isolates of Beauveria bassiana and Lecanicillium lecanii in this study were obtained from the collection of Insect Pathology Laboratory. Fungal suspension was innoculated to Tenebrio molitor adultsin order to increase the virulence after a long storage in the laboratory. Mycelia of the fungi from T. molitor cadavers were isolated and cultured on PDA (Potato Dextrose Agar) media, then colonies from PDA were subsequently transfered and maintained on rice media until± 21 days old. Fungi from this culture were used in this study. Bioassay were conducted with five levels of density, i.e. 105, 106, 107, 108 and 109 conidia/mL with ± 3 mL application volume for each treatment. Each treatment were made of four replicates. The number of larvae that were used for each replicate were 20 larvae, while the eggs treatment consistedof one egg mass per replicate. Probit analysis was used to analyze the mortality data and to estimate the value of LC. Result of this study indicated that B. bassiana with 109 conidia/mL caused 78.75% mortality of 2rd instar larvae, whereasthe same conidial density of L. lecanii caused 71.25% mortality. The value of LC50 were 1.39 x 106 conidia/mL for B. bassiana and 1.62 x 106 for L. lecanii; both LC values were calculated at 7 days observation. While 100% egg mortality was achieved by application of B. bassiana at 109 conidia/mL, the same degree of mortality could be achieved by L. lecanii at lower density,i.e. 108konidia/mL. Value of LC for both fungi against eggs at 3 days post treatment are 9.6 x 105 and 6.1 x 105 conidia/mL, respectively.
Keyword: conidia, density, eggs, larvae, mortality

Judul: Sudoku Tereduksi dan Grup Simetri Sudoku
Abstrak: Sudoku is a logic game in form of square games consisting rows, columns and mini grids. In this game, the square is filled by numbers from 1 to . At this game, the player plays the game precisely because each cell in a row or column should have a unique number. The mini grid should have no repeated numbers. This research proves that to determine the number of the isomorphic Sudoku solutions from given Sudoku solutions can be calculated using reduced Sudoku. Sudoku symmetry group is a collection of Sudoku solutions that is experienced symmetry group operations. Symmetry group operation is an operation permutation consisting permutation values, stack permutations, permutations band, column permutations on the stack, or row permutations of the band. The isomorphic Sudoku solutions from reduced Sudoku can be obtained from symmetry group operation imposed on Sudoku reduced. The total possible Sudoku solutions calculated from the number of given reduced Sudoku.
Keyword: sudoku symmetry group, reduced sudoku, isomorphic