Ochratoxin A concentrations from a total of 1223 samples from green, roasted and ground, decaffeinated and low acid and instant coffee analysed during 1995–1999 and 2000–2002 by German Official Food Control Laboratories were compared. Median concentrations, determined by statistical process analysis decreased within each group from the early group up to 2002. The rates of rejection were calculated on the basis of the recent data for green and roasted and ground coffee which may occur when particular maximum residue limits were set. Contamination rates from green coffee showed significant differences in their OTA concentrations depending on their geographical origin.

Ochratoxin A concentrations from a total of 1223 samples from green, roasted and ground, decaffeinated and low acid and instant coffee analysed during 1995-1999 and 2000-2002 by German Official Food Control Laboratories were compared. Median concentrations, determined by statistical process analysis decreased within each group from the early group up to 2002. The rates of rejection were calculated on the basis of the recent data for green and roasted and ground coffee which may occur when particular maximum residue limits were set. Contamination rates from green coffee showed significant differences in their OTA concentrations depending on their geographical origin.

Avoidance of occupied ovisposition sites supposes that females perceive information related to their own progency. Fatty acids identified from egg extracts have been reevaluated using a different extraction method, and we have investigated the dose-dependent oviposition response of European grape vine moths (Lobesia botrana) to myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, methyl palmitate, methyl oleate, and ethyl palmitate; all except ethyl palmitate have been identified from eggs ofL. botrana. A methylene dichloride extract of eggs fromL. botrana revealed the presence of saturated free fatty acids (myristic, palmitic, and stearic) and unsaturated acids (palmitoleic, oleic, linoleic, and linolenic) in amounts ranging from 3.9 ng/egg equivalent for myristic acid to 30 ng/egg equivalent for palmitic and oleic acids. The extract also contained traces of methyl palmitate and methyl stearate. The greatest avoidance indexes were observed in response to palmitic, palmitoleic, and oleic acids. All the other compounds tested caused weaker responses. A reduction in the number of eggs laid was observed when moths were exposed to each of the esters applied at 0.3 µg per application spot. Reduction in eggs laid was also observed at a 10-fold higher dose of oleic acid. The present results confirm that general and simple molecules can be involved in the regulation of oviposition site selection and that they may participate in chemical marking of the eggs.

This study compares the sensitivity of different phenological stages of grapevine cultivars to infestation by larvae of the European grapevine moth, Lobesia botrana Den. et Schiff. The fructiferous organs of six cultivars: Cabernet Franc, Merlot, Cabernet Sauvignon, Sauvignon, Semillon and Muller Thurgau were infested at 5-10 days intervals from the beginning of the vegetative period, with a constant number of newly hatched L. botrana larvae (five per organ). After the larvae reached the fifth instar, the fructiferous organs were cut and each grape analysed according to the damage. Each organ was classified into one of three groups: I - no damage; II - traces of probing activity and III - traces of feeding activity.At the beginning of the vegetative period (stages D and E) the percentage of fructiferous organs with traces of feeding activity is relatively low (20-35% dependent on cultivar). From stage F onwards the number of bunches with traces of feeding activity progressively increases, reaching a maximum at stage H (78-93%). In all cultivars tested a period was clearly observed when the fructiferous organs were significantly (ANOVA procedure, P < 0.0001) unsuitable for infestation by freshly hatched larvae, and this corresponded to phenological stages I and J (8-35% of bunches with traces of feeding activity). The phenological stages following stage J until harvest were again suitable for development of the larvae (50-95% of bunches in the group III), but with greater individual alter variability than observed for stages from F to H.

Codling moth females (Cydia pomonella, Lepidoptera: Tortricidae) (CM) usually lay single eggs and have a tendency to disperse. In a first experiment we observed that single females exposed to 20 apples distribute their eggs regularly among apples, suggesting a dispersive oviposition behavior. In a dual-choice situation, isolated females avoided oviposition on areas of cardboard treated with a methylene dichloride egg extract at the dose of ca. 1.0 egg equivalent/cm2. A strong avoidance was obtained in response to a 20-fold dose, which was accompanied by a significant reduction of total oviposition. Seven major compounds found by GC analyses in the methylene dichloride extract of 2 to 3-day-old eggs were saturated or unsaturated C14-C18 straight-chain fatty acids: myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. This was confirmed by GC-MS analysis of an extract made by ethyl ether. Smaller amounts of three methyl esters were also identified as methyl myristate, methyl palmitate, and methyl stearate. A blend of the seven fatty acids (FA) mimicked rather well the avoidance provoked by the extract, and this avoidance was confirmed by choice between treated and untreated fruits by single females. The treatment of apples with the 7FA mixture induced an aggregative distribution of the eggs among apples. We also found that the amounts of fatty acids harvested in the extract depend on the egg age. Amounts of fatty acids increased until eggs were 4 days old and then decreased before hatching. In this paper we discuss the possible role of simple molecules, such as fatty acids and their esters, as semiochemicals indicative of juvenile tissues.

The intention of this study was to falsify a hypothesis of interspecific avoidance of semiochemicals from egges by ovipositing tortricid females. The oviposition responses of Cydia pomonella (L.) females to apples baited with blends of semiochemicals identified in another tortricid species, Lobesia botrana (Den. et Schiff.) were investigated. Experiments were conducted in binary choice tests using natural oviposition substrates (apples). In each experimental arena, 4 mated females were offered 16 apples (8 treated and 8 untreated) and the number of egges was compared. Females avoid ovipositing on apples treated with a blend of nine components characteristic of methanolic extracts of L. botrana eggs (fatty acids and esters) (complete blend), as well as a binary blend of palmitic acid and methyl palmitate (binary blend). Oviposition avoidance was already observed with these two blends at a dose of 72 eggs equivalent of L. botrana per apple and this effect increased with the dose. The blend of three major esters from complete blend (ternary blend) did not provoke significant avoidance. In the control, only 8.3% of apples bore no egges, this percentage was increased with complete blend and binary blend (720 Lobesia eggs) respectively up to 37.5% and 26.4%, but only to 18.1% of apples with ternary blend. Complete blend and binary blend used at high dose strongly reduced the mean number of eggs/apple on treated fruits (1.6 ± 1.8; 9 compounds) (1.8 ± 2.2; 2 compounds) against 4.6 ± 4.0 in the control. This reduction was not observed with the blend of 3 esters. It is concluded that, from the present results, apples treated with compounds associated with L. botrana eggs are avoided by C. pomonella ovipositing females. Esters alone cannot explain such an avoidance, and palmitic acid may partly cause the avoidance response.

Females ofLobesia botrana Den. et Schiff. (Lepidoptera Tortricidae) are attracted in natural conditions by volatiles released by a nonhost plant: tansy (Tanacetum vulgare L.; Asteracea). We have shown that both tansy flowers and their odor inhibit oviposition behavior and mating behavior and reduce adult longevity. The mean number of eggs laid per female isolated with tansy flowers was reduced by up to 50% every 2 days during the 6 days of exposure. This reduction was maintained after the tansy was removed. In the presence of tansy essential oil, the egg-laying reduction ranged from about 30 to 80% according to the odor concentration. The number of spermatophores found in females isolated with tansy flowers was also reduced twofold compared to the control treatment, indicating that the presence of tansy reduced mating activity. This mating activity is strongly reduced, by two-thirds, when adults face the highest dose of essential oil compared to controls. The number of eggs laid by the controls cannot be explained by the number of spermatophores. Therefore, the reduction in oviposition has been attributed to the presence of tansy flowers or to the tansy odor. Tansy flowers and tansy odor increased male mortality during the exposure (10% in the control, 50% in the tansy treatment, and up to 98% in the odor treatment). The highest rates of male mortality occurred during the 4- to 6-day period of exposure to flowers or odor. Repellence resulting in sustained locomotor activity is a possible cause of such a mortality. Female mortality was increased only in response to the highest dose of odor. This increase might be due to egg retention, and not directly to a plant effect. We discuss the effects of tansy flower odor on different patterns relative to the reproductive behavior ofL. botrana and, especially, on oviposition behavior in the ecological context of plant selection and polyphagy.

Oviposition of four tortricid pests of vineyards (the European grapevine moth and the grape berry moth) and fruit orchards (the codling moth and the oriental fruit moth) is deterred by a blend of straight chain fatty acids and esters of fatty acids that have been identified in the eggs of one of them: the European grapevine moth (EGVM)Lobesia botrana. This is the first evidence of inter-specific recognition of an egg-like signal in moths. We demonstrate that oviposition site selection is influenced by population density, avoidance of deterrent being most important when females are isolated. Inter-specific egg recognition might be an important phenomenon, especially in species competing for a common food resource. We propose the term ‘oviposition regulating synomone’ for molecules and blends that affect the inter-specific spacing of eggs.

Dilauroyl and dimyristoylphosphatidylglycerol (DMPG) form a more stable gel state when aqueous suspensions are incubated several days at low temperature (0-2 degrees C), pH 7.4 with 0.15 M NaCl. This gel state is characterized by a higher transition temperature and a higher transition enthalpy. The geometry of this gel state is distinguishable from the metastable gel state that forms rapidly upon hydration on the basis of its x-ray diffraction pattern. Infrared spectra in the CH2 scissoring region indicate that the stable gel phase of DMPG is also characterized by reduced reorientational fluctuations of acyl chains and increased interchain interactions. Analysis of vibrational bands due to ester carbonyl groups of DMPG suggests that the transition to a new gel phase is initiated by changes in the interfacial and/or headgroup region of the bilayer, most likely via formation of interlipid hydrogen bonds. The melting of the stable gel phase of DMPG is accompanied by a gross morphological change resulting in vesiculation.

The oviposition of the European grapevine moth (EGVM) Lobesia botrana can be deterred by an extract of conspecific eggs corresponding to 20 egg equivalents. The reduction of the oviposition behavior is dose-dependent. Nine chemicals have been extracted from the eggs and identified as straight chain fatty acids and esters of fatty acids. A mixture of these rather simple molecules induces the same levels of deterrence as the total extract. It might be possible to use oviposition regulating pheromone in the future for the control of EGVM populations.

Extracellular purine nucleosides and nucleotides in micromolar concentrations stimulate proliferation of a variety of cell types in vitro and in vivo. As well they act synergistically with NGF to stimulate neurite outgrowth from PC12 cells. A variety of purine nucleosides and deoxyribonucleosides promote cell proliferation and increase intracellular cAMP. Their activities are inhibited by adenosine A2 receptor antagonists. Only adenosine interacts with the A2 receptor. We propose that the other nucleosides and deoxyribonucleosides inhibit extracellular adenosine deaminase, thereby increasing the extracellular concentration of adenosine. The nucleotides apparently act by stimulating P2y receptors coupled to inositol phosphate metabolism. We propose that the nucleosides and nucleotides act synergistically with other growth factors because each has distinct but complementary second messenger systems. If our hypotheses are correct, it should prove possible to modulate the growth and morphogenesis in several cell types using drugs that inhibit or stimulate adenosine A2 or purine P2y receptor agonists or the second messenger systems coupled to these receptors.

In natural conditions the attractiveness of tansy flowers Tanacetum vulgare L., was observed on the females of European grapevine moth, Lobesia botrana Den. & Schiff. The attraction is determined by comparing the number of females caught on grapevine and those caught on tansy flowers during a defined time interval. Oviposition and larval development never occurred on tansy, females flow to the flowers in order to take nectar or pollen. The physiological state of the adults is analysed after dissection. The reasons for the selection of the host plant by the polyphagous European grapevine moth and practical use of the observed natural phenomenon are discussed.

A circadian modulation of the behavioural activity of a number of insects such as Lepidoptera has already been described. This modulation is possibly induced by a combination of factors affecting both sensory perception and central nervous system excitability. Short-term and long-term variations of sensitivity in insect taste receptors in relation to feeding has been documented (Blaney et al., 1986). Moreover, long-term variations of olfactory sensitivity has been demonstrated in relation to age or reproductive state in some insect genera (Blaney et al., 1986). Although a diel variation in olfactory sensitivity to sex pheromones has not been found in Lepidoptera (Worster & Seabrook, 1989), electrophysiological experiments on nocturnal insects are often performed with insects reared in an inverted photoperiodic cycle.