Judul: Study of entomopathogenic fungi Lecanicillium lecanii (Zimm.) (Viegas) zare & gams to control pod sucking bug Riptortus linearis (F.) (Hemiptera: alydidae) Egg.
Abstrak: Lecanicillium lecanii (Zimm.) (Viegas) Zare & Gams is one of the most entopathogenic fungi that can be used to control pod sucking bug Riptortus linearis F. (Hemiptera: Alydidae) egg. The effectiveness of fungi were affected by intraspecies virulence, conidia density, host developmental stage, and environmental factors. The purposes of this research are: (1) to study the phisiological character of various L. lecanii isolates and their virulence to pod sucking bug R. linearis egg, (2) to obtain the maximal conidia density of L. lecanii to control different ages of R. linearis eggs, and (3) to study the effect of several vegetable oils as adjuvant to increase the effectiveness of fungi. Among 37 isolates tested, isolates Ll-JTM11, Ll-JTM12, Ll- JTM15, and Ll-TB2 were judged as the most virulent. The fungi that were virulent were isolated from insect cadaver killed by fungi in the field, while fungi isolated from the soil in general did not show high infectivity. The virulent isolates showed higher growth rate, formed wholly colony, produced more conidia than avirulent isolates, had large conidial size up to 6.5 x 2.5 ìm. More than 95% germ tubes of virulent isolates were formed after 12 hours incubation in the water. The conidia density of 108/ml was found as an effective preparation against newly laid and less than one day old insect eggs. During in vitro experiment, peanut, soybean, and coconut oil increased the growth and development of the fungi. The persistence of fungal conidia on the soybean leaf surface could be maintained until seven days after application. Mixing the vegetable oil at concentration 10 ml/l fungal suspension, increased infectivity of the fungi and decreased hatchability of the egg until 20%. Therefore, damage intensity as indicated by sum of spots, empty pods, and weight of grains were reduced. Adding vegetable oil to the fungal preparation, yielded 40% more grain weight as compared to control. Among three vegetable oils tested, the effect of peanut oil was more pronounced than soybean and coconut oil.
Keyword: Virulence, Soybean pod, Vegetable oils, Conidia

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: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf