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The flathead oak borer Coroebus undatus F. (Coleoptera: Buprestidae) is one of the primary pests of cork oak Quercus suber L. in the Mediterranean region causing great economic losses to the cork industry. Very little is known about its biology and behavior and, so far, no control measures have been established. We present the results of a pilot study aimed to develop an efficient trapping method for monitoring this harmful pest. In a 3-year field study, purple-colored prism traps baited with a mixture of green leaf volatiles (GLVs) from the host have been shown the most effective combination to catch C. undatus adults (solely females) compared to other trap and lure types tested. Wavelength and reflectance measurements revealed that purple traps exhibit reflectance peak values similar to those found in the abdominal and elytral cuticle of both sexes, suggesting the involvement of visual cues for mate location in this species. The data presented are the first to demonstrate captures of adults of the genus Coroebus by an attractant-based trapping method.

Outbreaks of locusts cause enormous economic losses to agriculture in many countries. To develop environmentally friendly strategies for their control, much research has been focused on the factors that influence locust biology, particularly infochemical-mediated interactions. We present herein the identification and synthesis of both Z and E isomers of phytal (3,7,11,15-tetramethylhexadec-2-enal, 1), which are involved in chemical communication and behaviour of the Moroccan locust, Dociostaurus maroccanus, a serious agricultural pest. The compound was identified by comparison of its chromatographic and spectrometric features and microchemical reactions with those of a synthetic sample. The natural compound was shown to have the R,R configuration by chiral HPLC analysis, and its structure is unique as an insect pheromone component. Both isomers of phytal are produced by sexually mature adult males and elicit electroantennographic responses in antennae of both sexes. In two-choice olfactometer bioassays, males and females significantly preferred the stream enriched with racemic phytal to the control. In contrast, hydrogenated phytal was behaviourally inert. Both isomers of phytal are specific to D. maroccanus as they are absent in the closely related, habitat-sharing species Dociostaurus jagoi and Calliptamus wattenwylianus. Legs and wings are the main release sites of the compound: approximately 90 % of that emitted by living individuals. In biosynthetic studies, phytal appears to proceed from oxidation of phytol (2) after injection of deuterated phytol into the abdomen of the insect or after administration in the diet. Our results demonstrate that phytal is a candidate sex pheromone component of the Moroccan locust; it is produced by mature males, and might be eavesdropped upon by conspecific males.

Department of Education, Universities and Research of the Basque Country Department of Agriculture and Fisheries of the Basque Country

There is currently relatively little information on how marine organisms process and analyze sound, making assessments about the impacts of artificial sound sources in the marine environment difficult. However, such assessments have become a priority because noise is now considered as a source of pollution that increasingly affects the natural balance of marine ecosystems. We present the first morphological and ultrastructural evidence of massive acoustic trauma, not compatible with life, in four cephalopod species subjected to low-frequency controlled-exposure experiments. Exposure to low-frequency sounds resulted in permanent and substantial alterations of the sensory hair cells of the statocysts, the structures responsible for the animals' sense of balance and position. These results indicate a need for further environmental regulation of human activities that introduce high-intensity, low-frequency sounds in the world's oceans.

Olfaction is essential for processing chemical signals in insects, but characterizing the proteins implicated in this process has proved challenging. We optimized 2-DE gel resolution of insect proteins by using a buffer containing two reducing agents, DTT and hydroxyethyl disulfide. This buffer clearly improved resolution and decreased spot streaking and spot trains of 2-DE in comparison to DTT alone. We described for the first time that the buffer with DTT and hydroxyethyl disulfide further to reducing streaking in the basic part of the gel eliminates false spots in the acidic gel regions that appeared when only DTT was used as reducing agent.

Most insect pheromones comprise multicomponent blends of geometric or optical isomers, and one major question is how insects produce species-specific ratios of components for successful reproductive isolation. Key enzymes suggested to be involved in pheromone biosynthesis are acetyl-coenzyme A carboxylase and fatty acyl synthetase, chain-shortening enzymes, desaturases, elongases, reductases, oxidases, and alcohol acetyl transferases. The female pheromone composition of the Egyptian armyworm Spodoptera littoralis (Boisd.) is highly dependent on the origin of the strain. In this review, we present a summary of the different reported pheromone compositions of the moth, including from our recent studies on this subject, as well as the biosynthetic routes to the different components and the molecular approaches involved. In addition, the key role played in the proposed biosynthetic pathways by a number of important biosynthetic enzymes, such as chain shortening enzymes, desaturases and alcohol acetyl transferases, is outlined, as well as the latest developments on the inhibition of these enzymes.

Toxic oil syndrome (TOS) is a disease that appeared in Spain in 1981. It affected more than 20 000 people and produced over 300 deaths in the first 2 years. In this paper, a prospective study on the differences in gene expression in sera between a control versus a TOS-affected population, both originally exposed to the toxic oil, is presented. Differential protein expression was analyzed by two-dimensional electrophoresis (2-DE). Several problems related with serum analysis by 2-DE were addressed in order to improve protein detection in the gel images. Three new commercial systems for albumin depletion were tested to optimize the detection of minor proteins that can be obscured by the presence of a few families of high abundance proteins (albumin, immunoglobulins). Other factors, such as the use of nonionic reductants or the presence of thiourea in the gels, were also tested. From these optimized images, a group of 329 major gel spots was located, matched and compared in serum samples. Thirty-five of these protein spots were found to be under- or overexpressed in TOS patients (> three-fold increase or decrease). Proteins in the differential spots were identified by matrix-assisted laser desorption/ionization-time of flight peptide map fingerprinting and database search. Several haptoglobin isoforms were found to be differentially expressed, showing expression phenotypes that could be related with TOS affection. Haptoglobin phenotypes have been previously reported to have important biological and clinical consequences and have been described as risk factors for several diseases.

The electrophysiological activity of some halogenated analogues of the major component of the sex pheromone of the corn stalk borer Sesamia nonagrioides Lef. (1) is presented. The analogues comprise a series of fluoro-, chloro- and bromoacetate analogues4–10 as well as trifluoromethyl ketone 11. The fluoro derivatives 4–6 displayed remarkable electro-antennogram (EAG) intrinsic activities in comparison with the parent acetate 1, while the remaining analogues elicited significantly lower response. The compounds have also been tested as inhibitors of the sex pheromone perception in EAG and in the field. In the laboratory. fluoro analogues 4–6 were better inhibitors than chloro derivatives 7–9, which in turn behaved similarly to the bromoacetate 10. Trifluoromethyl ketone 11, however, was a poor inhibitor of the pheromone action. In the field, baits of mixtures of compounds 5–11 with the corn stalk borer pheromone in 10:1 ratio inhibited the concomitant attraction of the clover cutworm moth Scotogramma irifolii Rott., while the difluoro analogue 5, trichloroacetate 9 and trifluoromethyl ketone 11 also diminished the number of catches of the armyworm Mythimna unipuncta Haw. The monofluoroacetate 4. trifluoro analogue 6 and bromo derivative 10 significantly disrupted the pheromone action of the corn borer, whereas trifluoromethyl ketone 11 synergistically increased the number of males attracted to the pheromone trap alone. Addition of 11 to baits containing the corn borer pheromone caught S. nonagrioides selectively with regard to the other habitat-sharing species M. unipuncta and S. trifolii.