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International audience; The most sustainable management of resistant varieties involves understanding which defence mechanisms the plant uses according to its resistance genes and stage of development and how effective these mechanisms are. Three grapevine varieties were compared for their susceptibility versus resistance to powdery mildew: Vitis vinifera 'Cabernet Sauvignon' (CS) and two hybrids, 'Artaban' and 'Prior'. Four different leaf ages were collected from 2-year-old grafted grapevines planted in pot or in vineyard, and several variables were assessed for each leaf: (a) morphological and physiological indicators, (b) pathogenicity traits: spore germination, infection ef?ciency, mycelial growth and sporulation, and (c) gene expression using a high-throughput quantitative reverse transcription PCR method to inform about plant defence status and functioning of primary metabolism. A significant decrease in germination and sporulation with increasing leaf age were observed for the three varieties: Prior showed a susceptibility similar to that of CS, whereas Artaban was fully resistant with no sporulation. Genes highlighted as markers of the variety were involved in defence (VvPR3, VvPR4 overexpressed in Artaban, VvPR4bis, VvAlli2 in Prior) or in primary metabolism (repression of VvCitS in Artaban, VvCHI in Prior, overexpression of VvCAD2, VvGST3 in Prior). After inoculation, more defence genes, especially PR proteins, were overexpressed in the oldest leaves as potential components of ontogenic resistance. PR proteins accounted for 25% of total disease variation. Phenylpropanoid and ethylene pathways were leaf age-dependent. The statistical method used highlighted the contributions of the genotypic expression involved in genetic (cultivar) and ontogenic (leaf age) resistances and of the metabolic pathways to the disease.

International audience; The increasing use of plant defense stimulators (PDS) and biostimulants (BS) to make agriculture more sustainable has led to questions about their action on plants. A new PhysBioGen approach is proposed with complementary tools: PHYSiological (root weight); BIOchemical and BIOlogical (secondary metabolite quantification and Plasmopara viticola development) and expressions of 161 GENes involved in metabolic plant functions. The proposed approach investigated the effects of three phytostimulants on Vitis vinifera: one PDS (ASM) and one BS chelated (CH) and another enriched with seaweed (SW). Distinct responses were obtained between the PDS and the two BS. In particular, we observed the persistence of anti-mildew efficacy over time, correlated with differentiated expressions of defense genes (VvROMT, VvSAMT, VvPR8). As expected, the two BS displayed more similarities to each other than to the PDS (flavonols, anthocyanins, free salicylic acid). However, the two BS revealed differences in the modulation of genes involved in defense and primary metabolism and some genes were identified as potential markers of their action (VvWRKY1, VvLOX9, VvPOD, VvPDV1, VvXIP1, VVDnaJ). Our results highlight the common and the specific effects of the two BS and the PDS. These new tools could help in understanding the mode of action of phytostimulants in order to achieve better quality and production yield and/or as a way to limit chemical inputs in the vineyard.

International audience; Grapevine is subject to diseases that affect yield and wine quality caused by various pathogens including Botrytis cinerea. To limit the use of fungicides, an alternative is to use plant elicitors such as benzothiadiazole (BTH). We investigated the effect of a fungicide (Pyrimethanil) and an elicitor (benzothiadiazole) on plant defenses. Applications for two consecutive years in the vineyard significantly reduced gray mold. Two and seven days after treatments, the expressions of 48 genes involved in defenses showed differential modulation (up- or down-regulation) depending on treatment. Some genes were identified as potential markers of protection and were linked to an increase in total polyphenols (TP) in leaves. Surprisingly, the fungicide also induced the expression of defense genes and increased the polyphenol content. This suggests that BTH acts as an efficient elicitor in the vineyard and that Pyrimethanil may act, in part, as a defense-inducing agent on the vine.

In many animals, male copulation is dependent on the detection and processing of female-produced sex pheromones, which is generally followed by a sexual refractory post-ejaculatory interval (PEI). In the male moth, Agrotis ipsilon, this PEI is characterized by a transient post-mating inhibition of behavioral and central nervous responses to sex pheromone, which prevents males from re-mating until they have refilled their reproductive tracts for a potential new ejaculate. However, the timing and possible factors inducing this rapid olfactory switch-off are still unknown. Here, we determined the initial time delay and duration of the PEI. Moreover, we tested the hypothesis that the brain, the testis and/or the sex accessory glands (SAGs) could produce a factor inducing the PEI. Lastly, we investigated the possible involvement of ecdysteroids, hormones essential for development and reproduction in insects, in this olfactory plasticity. Using brain and SAG cross-injections in virgin and newly-mated males, surgical treatments, wind tunnel behavioral experiments and EIA quantifications of ecdysteroids, we show that the PEI starts very shortly after the onset of copulation, and that SAGs contain a factor, which is produced/accumulated after copulation to induce the PEI. Moreover, SAGs were found to be the main source of ecdysteroids, whose concentration decreased after mating, whereas it increased in the haemolymph. 20-Hydroxyecdysone (20E) was identified as the major ecdysteroid in SAGs of A. ipsilon males. Finally, 20E injections did not reduce the behavioral pheromone response of virgin males. Altogether our data indicate that 20E is probably not involved in the PEI.

Benzothiadiazole (BTH), a salicylic acid analogue, strengthens plant defence mechanisms against a broad spectrum of pathogens. The role of pre-treatment with BTH in enhancing resistance against infection with various isolates of downy and powdery mildews (Plasmopara viticola and Erysiphe necator) was investigated in grapevine leaves. Tools were developed to better assess the defence status of the plant. In compatible interactions amongst a set of 19 genes, more than 57·2% of differentiated transcripts from P. viticola infected-leaves (Pv-infected leaves) and 90% from E. necator-infected leaves (En-infected leaves) were down-regulated at 24 h post-inoculation (hpi), indicating a manipulation of host responses by the pathogens. BTH treatment enhanced grapevine defences, with pathogen growth inhibited by 61–98%, depending on the pathogen isolate. Treatment also triggered up-regulation of pathogenesis-related protein genes such as PR-1, PR-2, PR-3, PR-8 and PR-10 in Pv-infected leaves, and PR-3, PR-6 and PR-10 in En-infected leaves. Treatment with BTH also led to regulation of indole pathway transcripts; in particular, anthranilate synthase was down-regulated at 24 hpi in all infected leaves, then strongly up-regulated afterwards according to the rate of pathogen development. Quantitation of polyphenols and stilbenes showed that pterostilbene was specifically accumulated in pre-treated leaves and associated with biological efficacy and significant increases in PR protein gene transcripts. The temporal evolution of defence-related genes in pre-treated infected leaves suggests that grapevine responses vary depending on the inter- or intra-species variability of pathogens.

BACKGROUND: Management of grapevine powdery mildewErysiphenecator Schw. requires fungicide treatments such as sterol demethylation inhibitors (DMIs) or mitochondrial inhibitors (QoIs). Recently, reduction in the efficacy of DMIs or QoIs was reported in Europe and the United States. The aim of the present study was to develop real-time qPCR tools to detect and quantify several CYP51 gene variants of E. necator: (i) A versus B groups (G37A) and (ii) sensitive versus resistant to sterol demethylase inhibitor fungicides (Y136F). RESULTS: The efficacy of the qPCR tools developed was better than the CAPS method, with a limit of 2 pg for En ecatorDNA, 0.06 ng for genetic group A and 1.4 ng for the DMI-resistant allele. The detection limits of qPCR protocols (LOD) ranged from 0.72 to 0.85%, and the quantification limits (LOQ) ranged from 2.4 to 2.85% for the two alleles G47A and Y136F respectively. The application of qPCR to field isolates from French vineyards showed the presence of DMI-resistant and/or QoI-resistant alleles in French pathogen populations, linked to genetic group B. CONCLUSION: The real-time PCR assay developed in this study provides a potentially useful tool for efficient quantification of different alleles of interest for fungicide monitoring and for population structure ofE.necator. c � 2010 Society of Chemical Industry

BACKGROUND: Management of strawberry powdery mildew, Podopshaera aphanis (Wallr.), requires numerous fungicide treatments. Limiting epidemics is heavily dependent on sterol demethylation inhibitors (DMIs) such as myclobutanil or penconazole. Recently, a noticeable reduction in the efficacy of these triazole fungicides was reported by strawberry growers in France. The goal of this study was to investigate the state of DMI sensitivity of French P. aphanis and provide tools for improved pest management. RESULTS: Using leaf disc sporulation assays, sensitivity to myclobutanil and penconazole of 23 isolates of P. aphanis was monitored. Myclobutanil EC50 ranged from less than 0.1 to 14.67 mg L−1 and for penconazole from 0.04 to 4.2 mg L−1. A cross-analysis and a Venn diagram showed that there was reduced sensitivity and a positive correlation between the less sensitive myclobutanil and penconazole isolates; 73.9% of isolates were less sensitive to a DMI and 47.8% exhibited less sensitivity to both fungicides. CONCLUSION: The results show that sensitivity to myclobutanil and, to a lesser extent, penconazole has become less efficient in strawberry powdery mildew in France. Therefore, urgent action is required in order to document its appearance and optimise methods of control. Copyright © 2009 Society of Chemical Industry

Original sequences and/or references used to find new candidate genes involved in grapevine defenses [26, 38, 52–63]. (DOCX 42 kb)

International audience; Biological control of Phaeomoniella chlamydospora, a pathogen involved in Esca, a grapevine trunk wood disease, was performed using the oomycete, Pythium oligandrum. Three 4-month greenhouse assays showed that necrosis of Vitis vinifera L. cv. Cabernet Sauvignon cuttings caused by P. chlamydospora was significantly reduced (40-50%) when P. oligandrum colonized the plant root systems. The expression of a set of 22 grapevine defense genes was then quantified by real-time polymerase chain reaction to determine plant responses in the interaction between P. oligandrum/. V. vinifera L./. P. chlamydospora. In the trunk, specific grapevine responses to the different treatments (control, P. oligandrum, P. chlamydospora and P. oligandrum+. P. chlamydospora treatments) were significantly differentiated. Expression levels of 6 genes associated with P. chlamydospora infection showed higher induction than when plants were pre-treated with P. oligandrum. These genes are involved in various pathways (PR proteins, phenylpropanoid pathways, oxylipin and oxydo-reduction systems). © 2015 Elsevier Inc.

Background The fight against grapevine diseases due to biotrophic pathogens usually requires the massive use of chemical fungicides with harmful environmental effects. An alternative strategy could be the use of compounds able to stimulate plant immune responses which significantly limit the development of pathogens in laboratory conditions. However, the efficiency of this strategy in natura is still insufficient to be included in pest management programs. To understand and to improve the mode of action of plant defense stimulators in the field, it is essential to develop reliable tools that describe the resistance status of the plant upon treatment. Results We have developed a pioneering tool (“NeoViGen96” chip) based on a microfluidic dynamic array platform allowing the expression profiling of 85 defense-related grapevine genes in 90 cDNA preparations in a 4 h single run. Two defense inducers, benzothiadiazole (BTH) and fosetyl-aluminum (FOS), have been tested in natura using the “NeoViGen96” chip as well as their efficacy against downy mildew. BTH-induced grapevine resistance is accompanied by the induction of PR protein genes (PR1, PR2 and PR3), genes coding key enzymes in the phenylpropanoid pathway (PAL and STS), a GST gene coding an enzyme involved in the redox status and an ACC gene involved in the ethylene pathway. FOS, a phosphonate known to possess a toxic activity against pathogens and an inducing effect on defense genes provided a better grapevine protection than BTH. Its mode of action was probably strictly due to its fungicide effect at high concentrations because treatment did not induce significant change in the expression level of selected defense-related genes. Conclusions The NeoViGen96” chip assesses the effectiveness of plant defense inducers on grapevine in vineyard with an excellent reproducibility. A single run with this system (4 h and 1,500 €), corresponds to 180 qPCR plates with conventional Q-PCR assays (Stragene system, 270 h and 9,000 €) thus a throughput 60–70 times higher and 6 times cheaper. Grapevine responses after BTH elicitation in the vineyard were similar to those obtained in laboratory conditions, whereas our results suggest that the protective effect of FOS against downy mildew in the vineyard was only due to its fungicide activity since no activity on plant defense genes was observed. This tool provides better understanding of how the grapevine replies to elicitation in its natural environment and how the elicitor potential can be used to reduce chemical fungicide inputs. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3304-z) contains supplementary material, which is available to authorized users.

International audience; The antagonistic activity of 46 bacterial strains isolated from Bordeaux vineyards were evaluated against Phaeomoniella chlamydospora, a major grapevine pathogen involved in Esca. The reduction of the necrosis length of stem cuttings ranged between 31.4% and 38.7% for the 8 most efficient strains. Two in planta trials allowed the selection of the two best strains, Bacillus pumilus (S32) and Paenibacillus sp. (S19). Their efficacy was not dependent on application method; co-inoculation, prevention in the wood and soil inoculation were tested. The involvement of antibiosis by the secretion of diffusible and/or volatile compounds in the antagonistic capacity of these two strains was assessed in vitro. Volatile compounds secreted by B. pumilus (S32) and Paenibacillus sp. (S19) were identified by gas chromatography/mass spectroscopy (GC/MS). The volatile compounds 1-octen-3-ol and 2,5-dimethyl pyrazine were obtained commercially and tested, and they showed strong antifungal activity against P. chlamydospora, which suggested that these compounds may play an important role in the bacterial antagonistic activity in planta. Furthermore, the expression of 10 major grapevine defense genes was quantified by real-time polymerase chain reaction, which demonstrated that the two strains significantly affected the grapevine transcripts four days after their application on the plants. High expression levels of different genes associated with P. chlamydospora infection in B. pumilus pre-treated plants suggests that this strain induces systemic resistance in grapevine. For the first time, we demonstrated the ability of two bacterial strains, B. pumilus and Paenibacillus sp., isolated from grapevine wood, to control P. chlamydospora via direct and/or indirect mechanisms.

Plot of Eigen values of the principal component Most of the variance in defense gene expression data set is contained in the first two principal components with ~ 60% of the total variability. (DOCX 76 kb)

In the European grapevine moth, Lobesia botrana (Denis and Schiffermuller) (Lepidoptera: Tortricidae), it has recently been shown that volatiles emitted from the main host plant, grapevine, are attractive to adult females. Here, using wind tunnel experiments, we tested the attractiveness of various grapevine, Vitis vinifera L. (Vitaceae), plant parts at different phenological stages, including ripe berries infested with the pathogenic fungus Botrytis cinerea (Persoon: Fries) (Sclerotiniaceae) to laboratory-reared virgin and mated male and female moths. We also tested the attractiveness of the non-host plant, tansy [Tanacetum vulgare (L.) (Asteraceae)], as flowers and flower volatiles were previously shown to be attractive to L. botrana females in the field. Mated female moths were the only adults to exhibit upwind orientation to grape plant parts in the flight tunnel. The most attractive parts of the grapevine plants were leaves, flower buds, and ripe berries. No attraction was observed to flowers. This corresponds to the phenological stages available when females of the 2-3 generations during a year are present in the field. No attraction was observed to leaves and flowers of tansy.

International audience; PBAN-like immunoreactivity has been detected in the suboesophageal ganglion and the brain (Br-SOG) of larvae and adult males and females of Agrotis ipsilon, using an antiserum against Helicoverpa zea PBAN (Hez-PBAN). The amino acid sequence of A. ipsilon PBAN (Agi-PBAN) was deduced from the cDNA sequence, using both Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) and 5' Rapid Amplification of cDNA Ends (RACE). The primers were degenerate sets of oligonucleotides derived from known amino acid sequences of the PBAN precursor. The final cloned fragment contained the complete DNA sequence coding for the putative Agi-PBAN. Based on a comparison with known PBAN processing from the polypeptide precursor, we propose that Agi-PBAN is a 33-amino acid peptide. Agi-PBAN exhibits high sequence homology with Hez-PBAN (88%), Lymantria dispar (Lyd-PBAN, 88%) and Bombyx mori PBAN (Bom-PBAN, 73%). Agi-PBAN shares the C-terminal hexapeptide sequence (Tyr-Phe-Ser-Pro-Arg-LeuNH(2)) with all identified PBANs but has only one methionine residue instead of two in Hez-PBAN and Lyd-PBAN, and three in Bom-PBAN. Based on predicted a.a. sequence, Agi-PBAN, with Leu-NH, as C-terminal motif, has been synthesized and assayed for its ability to promote pheromone production in decapitated females of A. ipsilon. Synthetic Agi-PBAN induced pheromone production in decapitated females as evaluated by the male responsiveness to the pheromonal blend in a wind tunnel.

Male sexual behavior of the black cutworm Agrotis ipsilon is controlled by corpora allata. Allatectomies performed on day-1 and day-3 males inhibited the typical sexual behavior in day-4 males when exposed to female pheromone in a wind tunnel. Both JH-III and JH-III acid were able to restore male sexual behavior, suggesting that corpora allata act through their endocrine activity. We demonstrated that corpora allata incubated in vitro produced only the acid form of JH-III and JH-II. Fluvastatin, an HMG-CoA reductase inhibitor, inhibited JH acid biosynthesis by the corpora allata when fluvastatin was added to incubation medium or injected in males 4 h before the bioassay. However, endocrine activity of CA resumed 5–6 h after injection, indicating that the effect of fluvastatin was temporary. Fluvastatin injection also induced temporary inhibition of male responsiveness. © 1996 Wiley-Liss, Inc.

Dufour-El Maleh Marie-Cécile. Barzakh : Fresque allégorique de Juan Goytislo. In: Horizons Maghrébins - Le droit à la mémoire, N°28-29, 1995. Juan Goytisolo : trajectoires. pp. 115-118.

Dufour-El Maleh Marie-Cécile, Masmoudi Abdelouhed. Présence de Walter Benjamin (Entretien). In: Horizons Maghrébins - Le droit à la mémoire, N°28-29, 1995. Juan Goytisolo : trajectoires. pp. 214-219.

International audience; The effectiveness of Quinone outside Inhibitor (QoI) fungicides against grape downy mildew in European vineyards has significantly decreased in the last decade. One nucleotide polymorphism, G143A in the cytochrome b gene of Plasmopara viticola, is involved in resistance to QoIs. Previous genetic examination on the mitochondrial genomes showed four major haplotypes (IR, IS, IIR, IIS) coexisting in European vineyards. A resistant allele (G143A) was present in IR and IIR haplotypes. The purpose of the present study was to estimate the diversity of the different mitochondrial haplotypes and their distribution in QoI-resistant populations before evaluating the potential cost of the resistant mutation G143A in P. viticola population. From 2000 to 2004, the frequencies of resistant isolates ranged from 0% to 23.25% with an average of 4.64 % among the populations examined. To evaluate the fitness of sensitive and resistant isolates, a comparison of different biological parameters including latent period, spore production and infection frequency was performed, enabling a fitness index (FI) to be determined. Resistant isolates exhibited greater infection frequency than sensitive isolates, whereas no significant difference was found in sporulation ability and latent period between sensitive and resistant isolates. To further investigate competitiveness among isolates, an assay including two resistant isolates in different proportion with a sensitive isolate was conducted on eight asexual growing cycles in the absence of a QoI fungicide. The competitiveness of resistant isolates varied according to their fitness parameters, suggesting that there is no noticeable cost of QoI resistance in controlled conditions in Plasmopara viticola.

Management of strawberry powdery mildew, Podopshaera aphanis (Wallr.), requires numerous fungicide treatments. Limiting epidemics is heavily dependent on sterol demethylation inhibitors (DMIs) such as myclobutanil or penconazole. Recently, a noticeable reduction in the efficacy of these triazole fungicides was reported by strawberry growers in France. The goal of this study was to investigate the state of DMI sensitivity of French P. aphanis and provide tools for improved pest management.Using leaf disc sporulation assays, sensitivity to myclobutanil and penconazole of 23 isolates of P. aphanis was monitored. Myclobutanil EC(50) ranged from less than 0.1 to 14.67 mg L(-1) and for penconazole from 0.04 to 4.2 mg L(-1). A cross-analysis and a Venn diagram showed that there was reduced sensitivity and a positive correlation between the less sensitive myclobutanil and penconazole isolates; 73.9% of isolates were less sensitive to a DMI and 47.8% exhibited less sensitivity to both fungicides.The results show that sensitivity to myclobutanil and, to a lesser extent, penconazole has become less efficient in strawberry powdery mildew in France. Therefore, urgent action is required in order to document its appearance and optimise methods of control.

Udgivelsesdato: 2009-Jun Male moths use sex pheromones to find their mating partners. In the moth, Agrotis ipsilon, the behavioral response and the neuron sensitivity within the primary olfactory centre, the antennal lobe (AL), to sex pheromone increase with age and juvenile hormone (JH) biosynthesis. By manipulating the JH level, we previously showed that JH controls this age-dependent neuronal plasticity, and that its effects are slow (within 2 days). We hypothesized that the hormonal effect might be indirect, and one neuromodulator candidate, which might serve as a mediator, is octopamine (OA). Here, we studied the effects of OA and an OA receptor antagonist, mianserin, on behavioral and AL neuron responses of mature and immature males during stimulation with sex pheromone. Our results indicate that, although OA injections enhanced the behavioral pheromone response in mature males, OA had no significant effect on behavior in immature males. However, mianserin injections decreased the behavioral response in mature males. AL neuron sensitivity increased after OA treatment in immature males, and decreased after mianserin treatment in mature males. Determination of OA levels in ALs of immature and mature males did not reveal any difference. To study the possible interactive effects of JH and OA, the behavioral pheromone response was analyzed in JH-deprived mature males injected with OA, and in immature males injected with fenoxycarb, a JH agonist, and mianserin. Results show that both JH and OA are necessary to elicit a behavioral response of A. ipsilon males to sex pheromone.

In both vertebrates and invertebrates, neurogenesis not only occurs during development but also persists throughout adult life. So far, adult neurogenesis has been detected in a few insect orders but not in Lepidoptera. In the moth, Agrotis ipsilon, the sensitivity of antennal lobe interneurons of males to sex pheromone is age- and juvenile hormone-dependent in accordance with changes in the behavioral response. As a first step to understand this neuronal plasticity, we tested the hypothesis that adult neurogenesis could occur in the moth brain using 5-bromo-2′-deoxyuridine injections on newly born and sexually mature moths. Our results show that persistent neurogenesis occurs in mushroom bodies of adult males and females of A. ipsilon. Two clusters of one to four neuroblasts in each brain hemisphere continue to divide in adult moths and give rise to small clusters of Kenyon cells in the cortex of the mushroom body calyces. Neurogenesis was observed in both newly born and sexually mature males. There was a clear increase in the number of newly born cells in brains as the time increased after the treatment that was performed soon after emergence. When treatments were performed in mature 3-day-old adults, neurogenesis was still detected in brains dissected 3 hours after treatment but was hardly visible 2 days later. Adult neurogenesis was also detected in the optic lobes but not in the antennal lobes. We hypothesize that the newly born neurons could play a role in the central nervous plasticity of olfactory processing in the adult moth A. ipsilon. J. Comp. Neurol. 495:635–643, 2006. © 2006 Wiley-Liss, Inc.

Mating is costly for both male and female insects and should therefore only occur if it is likely to be successful. Within one scotophase, which is the dark period of the light cycle, male moths can only produce one single spermatophore, which is transferred to the female during mating. Remating within the same scotophase would thus be unsuccessful. We tested the hypothesis that newly mated males of the moth Agrotis ipsilon have developed an energy-saving strategy based on the transient inhibition of their sexual behaviour, thus avoiding unsuccessful remating. Agrotis ipsilon males do not copulate more than once during the same scotophase. Moreover, newly mated males do not respond behaviourally to the female sex pheromone although electroantennograms showed that their peripheral olfactory system is fully functional. However, intracellular recordings of antennal lobe neurons showed that the sensitivity for the synthetic sex pheromone blend decreased as compared with that of unmated males. Both the sexual behaviour and the sensitivity of the antennal lobe neurons were restored when tested during the next scotophase. Our results show a fast, transient neuronal plasticity that 'switches off' the olfactory system, which could prevent males from mating unsuccessfully.

The involvement of both juvenile hormone acid (JHA) and the sex accessory glands (SAGs) in the reproduction of the male moth Agrotis ipsilon was studied as a function of age and mating status. Total protein content analysis followed by gel electrophoresis of the SAGs, radiochemical assay for JHA biosynthesis and surgical and behavioural experiments were performed. Both the protein content of the SAGs and the biosynthetic activity of the corpora allata (CA) increased with age. Allatectomy and JHA/JH treatments showed that the protein content of the SAGs is linked with the activity of the CA. The protein content of the glands, but not the rate of JHA biosynthesis, decreased just after mating, and both increased sharply 24 h later. Injection of fluvastatin, an inhibitor of JH biosynthesis, in males immediately after mating prevented the increase in JHA synthesis and lowered the total protein content of the SAGs. Moreover, fluvastatin disrupted normal spermatophore transfer during the next mating of the injected males. Our results show that JHA controls the reproduction of A. ipsilon males by its separate actions on the sex accessory glands and on sexual behaviour.

Dufour-El Maleh Marie-Cécile. Art et artisanat, figure double de la créativité. In: Horizons Maghrébins - Le droit à la mémoire, N°33-34, 1997. Itinérances. Art contemporain marocain. La question de la critique d'art. pp. 33-44.

Last-instar larvae of the corn stalk borer, Sesamia nonagrioides (Lep.: Noctuidae), enter a facultative diapause under short photoperiods. In this noctuid, diapause development is characterized by the ability of larvae to perform several larval moults (up to seven) before pupation. Surprisingly, these supernumerary moults were not stationary and larval growth did occur as shown by growth in head-capsule width and weight of diapausing larvae. These heavy diapause larvae produced heavier pupae than non-diapausing strains. The number of supernumerary moults varied for insects, although they were reared under the same conditions. Pupal weight of diapause larvae was independent of the number of supernumerary moults performed. Using a radiochemical assay, we show that corpora allata from Sesamia nonagrioides larvae produced juvenile hormone (JH) -III, JH-II and their respective diols and acids. Although corpora allata of day-4 diapause-destined larvae exhibited the same biosynthetic pattern, no labelled products could be detected in the incubation medium containing corpora allata from non-diapausing larvae of the same age. Biosynthetic activity of the corpora allata was detected throughout diapause.

Dufour-El Maleh Marie-Cécile. Une écriture sans destinataire ?. In: Horizons Maghrébins - Le droit à la mémoire, N°39, 1999. Place Jema' el Fna : Patrimoine Oral de l'Humanité. Héritage commun en Méditerranée. pp. 109-110.