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Abstract:Dung beetles are a functionally important component of most terrestrial ecosystems, but communities change with habitat disturbance and deforestation. In this study, we tested if dung beetle ensembles on dung of introduced cattle and of the endemic anoa, a small buffalo, are affected differentially by habitat disturbance. Therefore, we exposed 10 pitfall traps, five baited with anoa and five baited with cattle dung, per site in six habitat types ranging from natural and selectively logged rain forest to three types of agroforestry system (characterized by different management intensity) and open areas (n = 4 replicate sites per habitat type) at the margin of Lore Lindu National Park, Central Sulawesi, Indonesia. We found 28 species, 43% of which were endemic to Sulawesi. Species richness, abundance and biomass declined from natural forest towards open area. Large-bodied species appeared to be more sensitive to habitat disturbance and the ratio of large to small-sized dung beetles declined with land-use intensity. Although selectively logged forest and cocoa agroforestry systems had lower species richness compared with natural forest, they appeared to maintain a high portion of species originally inhabiting forest sites. The similarity of dung beetle ensembles recorded at forest and agroforestry sites reflects the high similarity of some habitat variables (e.g. vegetation structure and microclimate) between both habitat types compared with open areas. Species richness and abundances as well as species composition, which was characterized by decreases in mean body size, changed with land-use intensity, indicating that dung type is less important than habitat type for determining ensemble structure of these Indonesian dung beetles.

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The effects of tannins on survival, growth, and digestion were compared in two polyphagous species of Lepidoptera (one, the southern armyworm, a forb-feeder; and the other, the promethea silkmoth, a tree-feeder). Two different types of tannins (hydrolyzable and condensed) were incorporated into artificial basal diets in order to determine whether or not differential survival and growth would result between the forb feeder, which normally does not encounter tannins in its natural diet, and the tree-feeder, whose host species include many tanniniferous plants from several different families.Neonate larvae of the forb-feeding armyworms exhibited significantly suppressed 10-day growth rates at all tannin concentrations tested (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0% of wet weight) for both the hydrolyzable and the condensed tannin compared to the control diet, however no dose-effect was detectable. In contrast, there were no detectable differences in neonate survival or growth through the first 10 days for the tree-feeding promethea silkmoth larvae fed diets with either tannic acid or quebracho tree condensed tannin.In order to determine the physiological mechanisms of action of these tannins against armyworms, we conducted detailed physiological bioassays of biomass and nitrogen utilization by penultimate instar larvae. Standard gravimetric feeding studies with both tannic acid and the quebracho tree condensed tannin demonstrated that reduced relative growth rates (RGR's) of Spodoptera eridania Cram. were due to the suppressed relative consumption rates (RCR's) and decreased conversion efficiencies (ECD's) rather than due to digestibility-reduction (as reflected by approximate digestibility, AD). As with the neonate larval growth rate suppression, there were no detectable dose responses at the different concentrations of tannic acid (0.25, 0.50, 0.75, 1.00, 2.50, and 5.0 percent) and condensed tannins from quebracho (0.25, 0.50, 0.75, 1.0, and 2.5 percent) in our penultimate instar studies.

1 The expansion of agricultural fields is the main cause of landscape simplification and changes in the composition and configuration of landscapes. These landscape changes influence pests and their natural enemies, and may influence their interaction and the biological control services to which they contribute. However, the effects of landscape composition can vary between region and insect species. 2 The present study was conducted on cucumber plants in 16 different sites of varying landscape composition in Bogor and its surrounding area, West Java, Indonesia. Sampling of insects was performed on lepidopteran pests and their parasitoids. 3 The results obtained showed that landscape composition (i.e. patch number of cropland) had a positive impact on the abundance of parasitoids and their host (lepidopteran pests). Yet the proportion of natural habitat did not influence parasitoid abundance and their host-parasitoid interaction. The presence of Apanteles taragamae (i.e. the most abundant parasitoid) in the agricultural landscape was affected by the abundance of its hyperparasitoid and its host (Diaphania indica) and not by landscape composition. 4 The findings of the present study suggest that the higher proportion of patchy cropland in tropical agricultural landscapes, as well as agricultural practices, can maintain parasitoid abundance and functional diversity and, finally, an enhanced parasitism rate.

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Previous studies have shown leaves of tulip tree, Liriodendron tulipifera L. (of the Magnoliaceae) and of Populus tremuloides Michx. (of the Salicaceae) to be antixenotic/antibiotic to many Lepidoptera, including one of the most polyphagous of all phytophagous insects, the southern armyworm, Spodoptera eridania Cramer (Noctuidae). We investigated the physiological responses to this phytochemical activity on neonate and late instar armyworm larvae in controlled environments with particular emphasis upon the leaf extracts containing condensed tannins and hydrolysable tannins. These tannin-containing extracts of tulip tree leaves and quaking aspen leaves were generally toxic to neonate larvae. For later instars, growth suppression was not due to digestibility-reduction, but instead to suppressed consumption rates and greatly increased metabolic (respiratory) costs as reflected in reduced biomass conversion efficiencies.

Ekstrak tanaman dapat mempengaruhi fisiologi dan biokimia serangga yang meliputi penghambatan makan, asimilasi makanan, dan dan aktivitas enzim detoksifikasi, yaitu sitokrom b5 dan sitokrom P450. Penelitian ini bertujuan untuk menguji pengaruh ekstrak campuran Tephrosia vogelii : Piper aduncum (1 : 5) terhadap fisiologi Crocidolomia pavonana (F.) dan pengaruh ekstrak P. aduncum terhadap biokimia C. pavonana. Pengujian ekstrak campuran T. vogelii : P. aduncum (1 : 5) pada konsentrasi 0,06% atau setara dengan LC 95 menghambat makan larva C. pavonana hingga 94,82%. Ekstrak campuran yang diuji pada LC 25 (0,007%) dan LC 50 (0,014%) menyebabkan gangguan pertumbuhan relatif larva C. pavonana. Gangguan ini disebabkan oleh toksisitas intrinsik ekstrak campuran yang masuk ke dalam tubuh serangga. Selain gangguan pada pertumbuhan larva uji, juga terjadi peningkatan daya cerna serangga sebesar 11,11% sebagai bentuk adaptasi terhadap senyawa toksik tumbuhan. Adaptasi lain yang dilakukan larva C. pavonana adalah mekanisme detoksifikasi terhadap ekstrak P. aduncum. Hal ini tampak dari peningkatan aktivitas enzim oksidasi sitokrom b5 dan sitokrom P450 pada perlakuan in vivo dan in vitro jika dibandingkan dengan kontrol. Penelitian ini memberikan informasi mengenai cara kerja ekstrak campuran T. vogelii : P. aduncum (1 : 5) pada larva C. pavonana dan mekanisme detoksifikasi larva terhadap ekstrak P. aduncum. Key words: antifeedant, asimilasi, enzim, oksidasi, sitokrom ABSTRAKPlant extracts have been known to cause physiological and biochemical interferences against insect, such as feeding inhibitor, food assimilation, and changes on activity of cytochrome b5 and cytochrome P450. This study was carried out to examine the effect of the extracts mixture of Tephrosia vogeliiand : Piper aduncum (1 : 5) on the physiology of Crocidolomia pavonana (F.) as well as extract of P. aduncum on biochemical of C. pavonana. The study showed that larvae of C. pavonana was experiencing a feeding inhibition until 94.82% after treated with extracts mixture on concentration 0.06% or equivalent to LC 95 . However, larvae treated with extracts mixture on LC 25