The development of resistance to Bacillus thuringiensis toxic proteins is a growing concern because it could threaten both conventional and gene transfer use this environmentally safe biological insecticide. most common mechanism involves changes in binding affinity toxin receptors the insect midgut membrane. This has not been case Heliothis virescens. We have investigated proteolytic activity as possibility explain observed species. developed an improvement known methods demonstrate crude...

Abstract The western flower thrips Frankliniella occidentalis (Pergande) is a very significant pest of number different agricultural crops in the south‐east Spain. importance as not due mainly to direct damage inflicted on plant, but loss commercial value which occurs consequence development dark spots caused by tomato spotted wilt virus (TSWV) they transmit. economic threshold therefore almost zero, enhances problems resistance management. present work part global project that attempts...

Catalase (CAT), glutathione reductase (GR), S-transferase (GST), and thiobarbituric acid reactive substances (TBARS) were measured together with cadmium (Cd) toxicity accumulation in newly molted adults of Oncopeltus fasciatus (Dallas) exposed to the metal drinking water. Insects provided either 200 or 20 mg Cd/liter (96-h LC30 LC10, respectively) tap water for 1, 3, 5, 7 d. concentration accumulated Cd a time-dependent manner. Peroxilipids as TBARS significantly elevated (1.7- 1.9-fold)...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBiocidal activity of some Spanish Mediterranean plantsPascual Cunat, Eduardo Primo, Isidora Sanz, M. Dolores Garcera, Carmen March, William S. Bowers, and Rafael Martinez-PardoCite this: J. Agric. Food Chem. 1990, 38, 2, 497–500Publication Date (Print):February 1, 1990Publication History Published online1 May 2002Published inissue 1 February 1990https://pubs.acs.org/doi/10.1021/jf00092a036https://doi.org/10.1021/jf00092a036research-articleACS...

Abstract The western flower thrips, Frankliniella occidentalis (Pergande), is a serious pest in the south‐east of Spain owing to its direct feeding on crops, transmission tomato spotted wilt virus and very high level resistance insecticides. Mechanisms were examined using field populations F. with different susceptibilities acrinathrin, methiocarb (selective insecticides), endosulfan, metamidophos deltamethrin (broad‐spectrum insecticides). Esterase activity towards α‐naphthyl acetate p...

Abstract BACKGROUND: Frankliniella occidentalis (Pergande) is among the most important crop pests in south‐east region of Spain; its increasing resistance to insecticides constitutes a serious problem, and understanding mechanisms involved therefore great interest. To this end, F. populations, collected from field at different locations Spain, were studied terms total esterase activity isoenzyme pattern. RESULTS: Individual thrips extracts analysed by native polyacrylamide gel...

Two fractions obtained after chromatography of dichloromethane extract Penicillium brevicompactum culture medium showed anti-juvenile hormone activity. One was active when assayed in vivo against Oncopeltus fasciatus third-instar nymphs, whereas the other a strong vitro inhibition JH III biosynthesis on Locusta migratoria corpora allata. A subfraction latter, constituting 97% this fraction, is main component that possessed juvenile inhibitory Chemical characterization compound shows...

Abstract BACKGROUND: Western flower thrips (WFT), Frankliniella occidentalis (Pergande), is among the most important crop pests in south‐eastern region of Spain. Its increasing resistance to insecticides constitutes a serious problem, and understanding mechanisms involved therefore great interest. Use synergists inhibit enzymes insecticide detoxification widely used determine their responsibility for resistance. However, they do not always act as intended or expected, caution must be...

Three natural sesquiterpene lactones have been assayed for their biological activity on locust (Locusta migratoria) nymphs. Since results obtained in vivo pointed to disruptions juvenile hormone (JH)-regulated physiology, we tested the and a family of synthetic derivatives ability disturb rate JH biosynthesis by corpora allata (CA) vitro. All active compounds vitro share basic double-ring structure as well substituents with different chemical complexities. Compounds that shared an eudesmane...

Abstract Using polyacrylamide gel electrophoresis (PAGE) under denaturing conditions, two major polypeptides of 200,000 and 170,000 daltons were detected in the hemolymph mature female Oncopeltus fasciatus , but they not found males or newly emerged females. Those constituted bands early vitellogenic oocytes; however, absent from yolk eggs. The slower‐migrating band (200,000 daltons) appears to correspond a protein already identified O. whose synthesis has been suggested be independent...

The development of resistance to Bacillus thuringiensis toxic proteins is a growing concern because it could threaten both conventional and gene transfer use this environmentally safe biological insecticide. most common mechanism involves changes in binding affinity toxin receptors the insect midgut membrane. This has not been case Heliothis virescens. We have investigated proteolytic activity as possibility explain observed species. developed an improvement known methods demonstrate crude...

Two fractions obtained after chromatography of dichloromethane extract Penicillium brevicompactum culture medium showed anti-juvenile hormone activity. One was active when assayed in vivo against Oncopeltus fasciatus third-instar nymphs, whereas the other a strong vitro inhibition JH III biosynthesis on Locusta migratoria corpora allata. A subfraction latter, constituting 97% this fraction, is main component that possessed juvenile inhibitory Chemical characterization compound shows...

Summary— All the ganglia belonging to central nervous system of adults milkweed bug Spilostethus pandurus (Hemiptera) were screened immunohistochemically for vertebrate gastrin‐cholecystokinin (CCK‐8(s))‐like peptides. Several large reactive perikarya are present in median part protocerebrum, their processes extending dorsal ‘aorta’. These cell bodies also paraldehyde fuchsin‐positive, ie they A‐type cells. In lateral deutocerebrum and tritocerebrum, suboesophageal, prothoracic abdominal...