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Mosquitoes are known for their bites which caused discomfort and its role as vector for various dangerous diseases that has been the bane of humanity since antiquity. One of them is Culex quinquefasciatus which facilitates the spread of arbovirus and nematodes that caused debilitating impact for human life. To eliminate mosquito, the study for evaluating plant-based mosquito larvicidal extract of Cerbera odollam extract against C. quinquefasciatus was conducted. Twenty-five second instar of C. quinquefasciatus were subjected to the crude and fractionated extracts of C. odollam, and the larval mortality was observed at 24, and 48 h of exposure. The results showed that the crude extracts of leaves, rinds, and stem bark exhibited low larvicidal activities. Interestingly, crude extract of the seed kernel exhibited high larvicidal activity. We found that the fractionated extract derived from the seed kernel extract using ethyl acetate and n-hexane exhibited high larvicidal activities, suggesting that C. odollam extract could be promoted as a material for larval control.

Termite species diversity and assemblage structures differ in ecosystems and habitats. Termite distribution is also highly influenced by temperature, humidity and altitude. Greater species richness and greater density have been reported in humid forests than in arid or semiarid environments. However, termites biodiversity is known to be strongly affected by anthropogenic alteration, wich affect their functional assemblage structure. The humus-feeders were as the most sensitively affected, while the wood-feeders were the most resilient group among others. Therefore, the functional structures of termite communities in changing habitats and ecosystems are important subject to discuss in order to capture more understanding on termite and ecosystem relationship.

The wood-rot fungus is one of the most destructive organisms for wood, wood products and building structures besides termites and beetles. Until today, wood-root fungi are still difficult to control, so it is necessary to search for new natural ingredients to be developed as wood preservatives. The purpose of this study was to screen some plant extracts from the area surrounding Lake Toba as anti-wood-rot fungi. This study evaluated antifungal properties of 6 different plant extracts dissolved in methanol against 9 species of wood-rot fungi. The activity was determined using the method of Mohareb [1] by growing the fungi on PDA supplemented with the plant extracts. Parameters observed included diameter of fungal growth and inhibition percentage of fungal growth by plant extracts. Extracts of Tithonia diversifolia, Chromolaena odorata, Saurauia bracteosa dan Azadirachta indica displayed extraordinary activity in inhibiting the growth of wood rot, up to 100%, therefore these plant extracts have the potential to be further investigated as wood rot control agent.

To understand the effects of various dietary sources on the biological changes of a subterranean termite, Coptotermes formosanus Shiraki, the three lignocelluloses, i.e: softwood, hardwood, and grass with the different of samples shape/size (intact and powdered) were subjected to C. formosanus, and we analysed the biological changes of C. formosanus workers (survival, body mass and the presence of protists). The results showed that at the end of observation, the survival, body mass and presence of Pseudotrichonympha grassii and Holomastigotoides hartmanni in the guts when consumed wood diets were much higher than those of the termite workers when consumed rice culm straw diet, whereas the presence of Spirotrichonympha leidyi in the guts were similar for all the samples. We failed to detect significant difference between intact and powdered diets from each lignocellulose, suggesting that the difference of lignocellulose shape/size (intact and powdered) had no effect on the biological changes of a subterranean termite, C. formosanus.

Termite’s biodiversity is known to be strongly affected by disturbance, particularly in an urban area. The present study evaluated termite biodiversity and distribution in Batam Botanical Garden, an urban conservation area in Batam Island. In the surveyed area, termites could play a major beneficial role through the promotion of essential ecological processes in ecosystems, such as soil modification and rehabilitation; as well as their well-established role as pests for vegetation. Therefore, biodiversity evaluation of termite is very important to identify economically and ecologically important species. Termite survey had been conducted by a 100 × 2 m belt-transect. Transect area was divided into 20 sections (5 × 2 m), in which each section was surveyed for 30 minutes by two trained people. In total, 106 specimens (15 termite genera) were collected from three sampling sites: Plantation, Mangrove forest, and Forest.

Toba, North Sumatera is famous not only for its tourism destination but also for biodiversity. The aim of this research is to explore the potency of the local plant from Toba as bioinsecticide. Six local plant samples, which consists of genus Compositae, Meliaceae, Staphyleaceae, and Actinidiaceae, were obtained from the Toba region,. The macerated extracts were tested their insecticidal activity against Coptotermes gestroi and Spodoptera litura. Bioassay results showed that leaves extract of Ingul (Toona sinensis) at a concentration of 10% (w/v) had the highest mortality effect against Coptotermes gestroi on the tenth day of observation. Whereas, leaves extracts of Pirdot (Saurauia bracteosa), Ingul (Toona sinensis), and Haurese (Azadirachta indica) at the concentration of 1% (w/v) showed the best insecticidal effect with 80% mortality percentage respectively against Spodoptera litura in 4 hours of observation.

Ectoparasitic fungi grow on the body surface of termites, and they might effect on behavior, reproductive, and survival of host termites. There are two common species of ectoparasitic fungi found on termite:Laboulbeniopsis gallicaThaxt andAntennopsis gallicaBuchli and Heim. In this study, the distribution ofL. termitariusandA. gallicainReticulitermesspp. colonies in Japan was observed. Meanwhile, the infection rate and strength ofL. termitariusandA. gallicawere discussed with references to the effects of environmental factors at the collections sites. In a total of 63 colonies ofReticulitermesspp. were collected from seventeen locations (from Hokkaido Prefecture to Okinawa Prefecture) in Japan. Five hundred workers and twenty soldiers from each colony were examined individually to see the infection ofL.termitariusandA.gallica. The survey showed thatL.termitariusdistributed in whole Japan andA.gallicahad a little bit restricted distribution. The infection rate of workers ofReticulitermesspp. varied among all locations: 0.10 – 16.10% for L.termitariusand 0 – 66.40% for A.gallica.No infected soldiers were observed. The negative relationship between temperature and infection rate was speculated in both fungi. Rearing the colonies in the laboratory might result in the spreading of the fungi in the colonies. Both fungi grew on any body parts of the termites. The trials for isolation and cultivation ofLaboulbeniopsis termitariusand A.gallicawith eight media did not succeed under the laboratory conditions.