Abstrak Penelitian ini bertujuan menguji efektifitas ekstrak daun sirsak dan daun gamal sebagai pengendali hama walang sangit  pada tanaman padi. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan 2 perlakuan yaitu jenis ekstrak dan konsentrasi ekstrak. Perlakuan 1 yaitu jenis ekstrak daun (A): sirsak (A1) dan gamal (A2), perlakuan 2 yaitu konsentrasi ekstrak (K): Kontrol (K0), 5% (K1), 10% (K2), 15% (K3), dan 20% (K4). Hasil penelitian menunjukkan bahwa ekstrak daun sirsak efektif terhadap mortalitas walang sangit tertinggi pada konsentrasi 20% (83%) dan yang terendah pada konsentrasi 0% (0 %). Ekstrak daun gamal juga efektif terhadap mortalitas walang sangit tertinggi pada konsentrasi 20% (74%) dan yang terendah pada konsentrasi 0% (0%). Waktu kematian pada hari pertama setelah aplikasi dengan rata-rata mortalitas tertinggi berada pada perlakuan ekstrak daun sirsak 20% (30%) dan daun gamal 20% (28%) dan terendah berada pada perlakuan ekstrak daun sirsak 0% (0%) dan daun gamal 0 % (0%). Kata kunci: daun gamal, daun sirsak, tanaman padi, walang sangit Abstract This study aimed to evaluate the effectiveness of soursop leaf extract and gliricidia leaves as pest control of walang rice (L. acuta) in the rice plants. This study used a completely randomized design (CRD) with 2 treatments, i.e. extract type and extract concentration. The treatment of extract type (A) were soursop (A1) and Gamal (A2), whereas the treatment  of extract concentration (K) were control (K0), 5% (K1), 10% (K2), 15% (K3), and 20% (K4). The results showed that the soursop leaf extract was effective to control sangit walang with the highest mortality was in the concentration of 20% (83%) and the lowest was in the concentration of 0% (0%). Gliricidia leaf extract was also effective to control sangit walang with the highest mortality in the concentration of 20% (74%) and the lowest was in the concentration of 0% (0%). The mortality time was on the first day of the application with the average highest mortality was in the treatment of 20% soursop leaf extract  (30%)and 20% gliricidia leaves (28%) respectively. The lowest mortality was in the treatment of 0% soursop leaf extract (0%) and 0% gliricidia leaves (0%).Keywords: gliricidia leaves, rice plant, soursop leaves, walang rice pest

Antimicrobial resistance is a major public health and development concern on a global scale. The increasing resistance of the pathogenic bacteria Neisseria gonorrhoeae to antibiotics necessitates efforts to identify potential alternative antibiotics from nature, including insects, which are already recognized as a source of natural antibiotics by the scientific community. This study aimed to determine the potential of components of gut-associated bacteria isolated from Apis dorsata, an Asian giant honeybee, as an antibacterial against N. gonorrhoeae by in vitro and in silico methods as an initial process in the stage of new drug discovery. The identified gut-associated bacteria of A. dorsata included Acinetobacter indicus and Bacillus cereus with 100% identity to referenced bacteria from GenBank. Cell-free culture supernatants (CFCS) of B. cereus had a very strong antibacterial activity against N. gonorrhoeae in an in vitro antibacterial testing. Meanwhile, molecular docking revealed that antimicrobial lipopeptides from B. cereus (surfactin, fengycin, and iturin A) had a comparable value of binding-free energy (BFE) with the target protein receptor for N. gonorrhoeae, namely penicillin-binding protein (PBP) 1 and PBP2 when compared with the ceftriaxone, cefixime, and doxycycline. The molecular dynamics simulation (MDS) study revealed that the surfactin remains stable at the active site of PBP2 despite the alteration of the H-bond and hydrophobic interactions. According to this finding, surfactin has the greatest antibacterial potential against PBP2 of N. gonorrhoeae.

Bedbug is the major pest in paddy fields in North Sulawesi. The pest attacks on vegetative and generative phase of rice . The species  of pest  attacking on  paddy fields in North Sulawesi is unknown. The study aimed to evaluate  the spread of bedbug ground pests, to identify the pest species as well as natural enemies of the pest at  the ecosystem of paddy fields in North Sulawesi. The result showed that the pest had spread to paddy field in Bolaang Mongondow, South Minahasa and Southeast Minahasa. In Minahasa regency, the pest had not been detected. In terms of population density of pest bugs , the highest was  found in  Bolaang Mongondow which was 14.67 individual per 20 times of swinging  followed by South Minahasa which was 10.33 individual. The lowest was found in Southeastern Minahasa which was 0.67 individuals. There were eight types of natural enemies of the pest  in  soil ecosystem of paddy fields in North Sulawesi. The eight types of natural enemies of the pest were  seven  predator and one parasitoid. The one parasitoid was Telenomus sp. The  seven predator were  Micraspis crocea, Methioche sp, Anaxipha sp, Oxyopes javanus, Tetragnatha sp, Lycosa sp and Chilomenes sp. Keywords: bedbug spread of soil, its natural enemies

Abstrak   Kupu-kupu merupakan salah satu bagian dari ekosistem yang fungsinya mempertahankan keseimbangan ekosistem dan memperkaya keanekaragaman hayati. Tujuan penelitian yaitu untuk menganalisis kekayaan, kelimpahan, keanekaragaman dan kemerataan spesies di hutan Danowudu, Masarang dan Kawatak, juga membandingkan jenis kupu-kupu berdasarkan topografi pada ketiga lokasi hutan tersebut. Penelitian ini dilaksanakan di hutan Danowudu, Masarang dan Kawatak dan dilanjutkan di laboratorium dari bulan Maret-Juli 2016. Penelitian ini menggunakan metode transek dan rute dibuat sepanjang 1000 m untuk setiap transek. Hasil penelitian menunjukkan bahwa kelimpahan, kekayaan dan keanekaragaman spesies kupu-kupu tertinggi di hutan Danowudu. Kemerataan spesies tertinggi di hutan Masarang. Spesies kupu-kupu yang hanya dapat ditemukan di hutan Danowudu (200-240 mdpl) terdiri dari 13 spesies. Spesies kupu-kupu yang hanya dapat ditemukan di hutan kawatak (827-938 mdpl) terdiri dari 7 spesies. Spesies kupu-kupu yang hanya dapat ditemukan di hutan Masarang (1084-1194 mdpl) terdiri dari 3 spesies. Kata kunci: keanekaragaman, kupu-kupu, Lepidoptera, Sulawesi Utara   Abstract   Butterfly is part of an ecosystem and has function to maintain ecosystem stability and enrich biodiversity. This research aimed to analyze the richness, abundance, diversity and evenness of species in Danowudu, Masarang and Kawatak forest as well as to compare the species of butterflies based on the topography of the three locations of the forest. This research was conducted in Danowudu, Masarang and Kawatak forest and the continued in the laboratory from March to July 2016. This study used a transect method and the route was made as long as 1000 m for each transect. The results showed that the highest abundance, richness and diversity of butterfly species were in Danowudu forest. The highest evenness of species was in the Masarang forest. Butterfly species that was only found in Danowudu forest (200-240 masl) consisted of 13 species. Butterfly species that was only found in Kawatak forest (827-938 masl) included 7 species. Butterfly species that was only found in Masarang forest (1084-1194 masl) comprised 3 species. Keywords: butterfly, diversity, Lepidoptera, North Sulawesi

Brown planthoppers have been reported to be resistant to various types of insecticides. One of the environmentally friendly controls is the use of entomopathogenic fungi. This study aims to test the effectiveness of the entomopathogenic fungus M. huainamdangense local isolates against brown planthoppers. Pathogenicity testing of local isolates of M. huainamdangense used a completely randomized design (CRD) with five treatments, namely K1 (Density 106), K2 (Density 107), K3 (Density 108), K4 (Density 109) and K0 as control. Each treatment was repeated 5 (five) times. The results showed that the fastest treatment to kill insects up to 100% was in the K4 treatment (density 109). The results of the probit analysis showed the LT50 value in the conidium density treatment 109 (K4) at 1.6 days. Meanwhile, the LC50 value showed a concentration of 108.9 conidium/ml on the second day. The use of a lower concentration of conidia density was able to kill 50% of insects in a longer time. Keywords: Metarhizium huainamdangense; entomopathogen; Nilaparvata lugens ABSTRAKWereng coklat telah dilaporkan resisten terhadap berbagai jenis insektisida. Salah satu pengendalian yang ramah lingkungan, yaitu dengan penggunaan jamur entomopatogen. Penelitian ini bertujuan untuk menguji keefektifan jamur entomopatogen M. huainamdangense isolat lokal terhadap wereng coklat. Pengujian patogenisitas isolat lokal M. huainamdangense menggunakan Rancangan Acak Lengkap (RAL) dengan lima perlakuan yaitu perlakuan K1 (Kerapatan 106), K2 (Kerapatan 107), K3 (Kerapatan 108), K4 (Kerapatan 109) dan K0 sebagai kontrol. Setiap perlakuan diulang 5 (lima) kali. Hasil penelitian menunjukkan bahwa perlakuan yang paling cepat mematikan serangga hingga 100% yaitu pada perlakuan K4 (Kerapatan 109). Hasil analisis probit menunjukkan nilai LT50 pada perlakuan kerapatan konidium 109 (K4) yaitu pada 1,6 hari, sedangkan nilai LC50 menunjukkan konsentrasi 108,9 konidium/ml pada hari kedua. Penggunaan konsentrasi kerapatan konidia yang lebih rendah mampu mematikan 50% serangga dalam waktu yang lebih lama. Kata kunci: Metarhizium huainamdangense; entomopatogen; Nilaparvata lugens