A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae ...

The jasmonate pathway is a highly conserved defensive cascade in plants that regulates the induction of resistance against herbivores; however, its role in herbivore feeding behaviour remains unknown. We used a mutant tomato plant ( def -1) deficient in the production of jasmonate-related defensive proteins to test the hypothesis that genotypes with a reduced ability to induce resistance have a...

Experiments were conducted to assess the effects of the entomopathogenic nematode Steinernema carpocapsae and Spodoptera exigua multinucleocapsid nuclear polyhedrosis virus (SeMNPV), alone and in combinations, on mortality of the beet armyworm, S. exigua, larvae on soybean. In 1991 tests, field-grown soybean plants were treated with S. carpocapsae at 0.3 and 0.6 nematodes/cm(2) of leaflet, SeMN...

Marasmia exigua (Butler) (Lepidoptera: Pyralidae) is one of the major rice leaffolders negatively affecting the rice production in the world. The growth and development of M. exigua was studied at seven constant temperatures (10, 15, 20, 25, 27, 30 and 35°C). The results showed that M. exigua eggs failed to hatch at 10°C and the larvae could not complete development at 15 and 35°C. The developm...

life table parameters of the beet armyworm, spodoptera exigua (hã¼bner), on four sugar beet cultivars (renger, fd0005, dorothea and shirin) were studied in laboratory at 27 â± 1â°c, 60 â± 5% rh and a photoperiod of 16l: 8d hours. the larvae successfully developed on all cultivars. the shortest and longest total developmental time were recorded on fd0005 and renger, respectively. the development...

The importance of the double bonds in the furan ring of avocadofurans with relation to their insecticidal activity was examined. The insecticidal activity of two naturally occurring avocadofurans, 2-(pentadecyl)furan and 2-(heptadecyl)furan, was compared to the toxicity of five tetrahydrofurans with alkyl chains at position 2 and varying side chains from 14 to 18 carbons. We found that eliminat...

Anton Dohrn was introduced to Darwinism by Ernst Haeckel during his student years at Jena, and became an eager disciple of Charles Darwin's work. He founded the Stazione Zoologica in 1872. Darwin became a patron of Dohrn's Stazione, and the two naturalists corresponded regularly. This article discusses their relationship and the contributions of Christiane Groeben to its elucidation.

Glutaredoxins (Grxs) are a class of small, heat-stable, acidic proteins which have been implied in various biological activities cells, including the defense against oxidative stress induced by biotic and abiotic factors. In this paper, effects RNAi targeting SeGrx1 on cytotoxicity insecticide susceptibility camptothecin (CPT) Spodoptera exigua were investigated. Results showed that CPT to cell...

Five different combinations of fluorescent tubes (UV-B/UV-B, UV-B/UV-A, UV-A/ UV-A, UV-B/White, White/White) were used to determine relative effects of UV and visible light on the nucleopolyhedroviruses (NPV) of Helicoverpa zea and Spodoptera exigua. For both viruses, the greatest inactivation occurred with exposure to UV-B radiation. Both virus concentration and radiation exposure time influen...

Many parasites manipulate host behaviour to enhance parasite transmission and survival. A fascinating example is baculoviruses, which often induce death in caterpillar hosts at elevated positions ('tree-top' disease). To date, little is known about the underlying processes leading to this adaptive host manipulation. Here, we show that the baculovirus Spodoptera exigua multiple nucleopolyhedrovi...