DOCTORAL DISSERTATION (PhD) THESES. UNIVERSITY OF PANNONIA GEORGIKON FACULTY Plant Cropping and Horticulture Scienses PhD School

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1 DOCTORAL DISSERTATION (PhD) THESES UNIVERSITY OF PANNONIA GEORGIKON FACULTY Plant Cropping and Horticulture Scienses PhD School Dissertation advisor: Miklós Nádasy, Ph.D., C.Sc. Consultant: Gábor Szőcs, Ph.D., C.Sc. OBSERVATION OF CALLING BEHAVIOUR, ISOLATION OF FEMALE-PRODUCED SEX PHEROMONE OF THE HONEY LOCUST GALL MIDGE (DASINEURA GLEDITCHIAE OSTEN SACKEN), AND DEVELOPMENT OF A SYNTHETIC TRAP BAIT FOR PRACTICAL MONITORING by PÉTER BÉLA MOLNÁR KESZTHELY 2011

2 Illustration of the female and male honeylocust gall midge (Dasineura gleditchiae) (Zsuzsa Benedicty) 1.1. Scientific background 1. SCIENTIFIC BACKGROUND AND OBJECTIVES The gall midges (Cecidomyiidae, Diptera) are a species-reach family in which more than 5000 species are described, many of these are important agricultural pests. Despite of their tiny size they can cause considerable damage in many different crops, worldwide. Because they damage reproductive parts of the plant, they can cause significant yield reduction. This damage may be particularly important in case of the cereals, grown in developing countries of Africa and Asia, caused by rice gallmidge or sorghum gallmidge. The adults have short lifespan, therefore a control measure against them would require exact timing. The larvae develop inside the host plant, also surface application of pesticide can not reach them. All these make difficult to control the pest. Honeylocust gall midge (Dasineura gleditchiae Osten Sacken) was introduced from North- America to Europe. This pest is monophagus. Females prefer to ovipositor on the unextended leaflets of the shoots of the honeylocust tree (Gleditsia triacanthos L.). Freshly emerged larvae when start to eat induce the forming of galls. During the vegetation period the larvae pupate inside the galls. Finally, after emerging of adults the galls dry out and fall down, so the shoot loses its leaves. The aesthetic value of the trees decrease, and the shoots become more sensitive to frost Scientific objectives The chemical communication of this gallmidge species was completely unknown, including the chemical composition of its sex pheromone. In order to identify its sex pheromone with a final aim of developing a pheromone trap which could be used to monitor the flight of this pest, we initiated a complex study. The objectives of my studies were: to observe the calling behavior of the honey locust gall midge to observe the mating behavior to observe the diel dependence of mating to extract the sex pheromone to search for pheromone component(s) by means of gas chromatography with coupled electroantennographic detector If all these, plus the structure elucidation and synthesis of the antennaly active component(s) successfully completed, then to optimize a bait used in traps for monitoring 2

3 2. MATERIALS AND METHODS Experiments were carried out at the Zoological Department, Plant Protection Institute of Hungarian Academy of Sciences (Budapest), unless otherwise stated Experimental insects Gall midges were collected as mature larvae or pupae inside the galls on infested leaves of G. triacanthos located in Budapest. Infested leaves were placed onto pieces of filter paper, inside cylindrical glass containers (15 cm diameter, 20 cm high), in the laboratory. Containers were covered by a layer of textile and Petri-dish to keep the humidity inside. Containers were placed at room temperature (24 C) under 18:6 hours L:D photoperiod at a relative humidity 80-90%. During 8:00 AM to 1:00 PM an additional light (500 W Hg) were used. Freshly emerged adults were separated by sex on the basis of the morphological differences in their antennae and abdomen. Females mate in the morning hours of the day of emergence. Thus, midges were collected early in the morning, and assumed to be unmated Observation of calling behaviour, diel dependence and length of mating Beside the outdoor observations, laboratory observations were also conducted using freshly emerged adults. Behaviour tests were conducted in a greenhouse with an open wall to imitate ambient conditions. A single female was placed in a Petri-dish (20 cm diam) containing a freshly cut leaflet of G. triacanthos Sunburst, and allowed to acclimatize for a few minutes Then, 5 males were introduced into the Petri-dish (25 replicates). The freshly emerged females were observed from 7:00 am to 4:00 pm continuously. Copulatory behavior was observed, and the duration of copula measured. For statistical analyses, an unpaired t-test was used Colletion of sex pheromone To collect the female emitted (airborne) sex pheromone, a volatile collection method was used, utilizing a closed loop stripping apparatus (CLSA) (Brechbüler, AG, Schlieren, Swietzerland). A special, inert pump circulated the air in the closed glass tube system and the compouds were absorbed by activated carbon adsorbent (1.5 mg). The sex pheromone was collected continuously for three days on the same activated carbon adsorbent, which was finally eluted using n-hexane. For preparing the strongest extract, altogether 1800 female honey locust gall midges were used. The extracts were stored in sealed glass pipettes on minus 60 C Electroantennographic analysis of collected volatiles and synthetic compounds (EAG and GC- EAD) The electroantennographic activity of the collected volatiles was verified by using electroantenograph (EAG). EAG responses were recorded with glass electrodes (1.17 mm i.d.; Syntech, Hilversum, The Netherlands) pulled to a fine point and filled with Beadle-Ephrussi Ringer solution. These were attached to silver/silver chloride electrodes held in MP15 micromanipulator and connected to an IDAC 232 amplifier (Syntech). The reference electrode was inserted into the ventral part of the isolated head of a male D. gleditchiae, and the intact tip of one antenna was inserted into the recording electrode, which was cut to give a close fit. The required amount of natural pheromone or synthetics dissolved in hexane (10 µl) were applied to a piece of filter paper (1 x 1 cm). The natural pheromone was quantified by gas chromatography with flame ionization detector, based on comparison of the area of the peak on GC trace corresponding to the EAG active component with those of standard acetates. Stimuli were delivered by puffing air (1 ml) through a Pasteur pipette that contained the filter paper into a moistened air stream (660 ml/min) directed towards the antenna. The series of stimuli was tested on 5 antennal preparations. For statistical 3

4 analysis, responses to synthetic samples were normalized to the responses evoked by an aliquot of volatile colletion containig ca. 2.8 ng of natural pheromone, corresponding to ca. 150 females equivalent hours (FEH). Data were transformed to log(x+1), and subjected to ANOVA. If the F value was significant, differences between means were tested for significance by Games-Howell post-hoc test, using the program SuperANOVA (Abacus Concepts Inc., Berkeley, CA, USA). The retention time of the pheromone in the volatile colletion was determined using a gas chromatography (Agilent 6890N, Agilent Technologies Inc., Santa Clara, CA, USA) coupled to electroantennographic detection (GC-EAG) (Syntech). The gas chromatograph was used with DB- WAX capillary column 30m x 0.32mm x 0.25µm film thickness (J&W Scientific) in sliptless injection mode (on 220 C inlet temperature) operated with the following temperature programme: 60 C for 1 min, than 10 C/ min till 220 C and finally 220 C for 20 min. The carrier gas was helium (4.0 ml/min). Decenil-acetate (S10:Ac) was used as internal standard. The antennal detector of this set-up was exactly the same as described above. 2.5 Gas chromatography linked to mass spectroscopy (GC-MS) (Natural Resourses Insitute, Univerity of Greenwich, Chatham Maritime, UK) (NRI) The structure of the component, pinpointed by the retention time and retention index of the antennal response in the GC-EAD runs (the supposed sex pheromone), was stereochemically elucidated by GC-MS measurements, by Prof. David R. Hall (NRI). The identified compound was synthesized by the same lab. As a result of the stereoselective synthesis the pheromone was produced in 99,1% and its antipode in 99,0% enantiomeric excess Field trapping tests with synthetic compounds Synthetic compounds were applied to red rubber dispensers (MSZ 9691/6, TAURUS, Budapest, Hungary) in hexane (20 µl). Delta-shaped traps with transparent walls (Csalomon RAG, Plant Protetion Institute, Hungarian Academy of Sciences, Budapest, Hungary) were used with exchangeable insert (10 x 16 cm) coated with adhesive (Tangle Trap, Tanglefoot Co., Grand Rapids, MI, USA). Traps were placed in the foliage of G. triacanthos Sunburst trees at Lágymányosi híd, Budapest, Hungary 2 m above ground and 10 m apart from each other. In the first experiment, catches of traps baited with either racemic (Z)-2-acetoxy-8-heptadecene (20 µg) or (R)- or (S)-enantiomers (10 µg) were compared. The layout was a randomized complete block design, with 7 replicates. The trial ran from 1-3 June In a subsequent experiment, the enantiomeric ratio (95:5 R:S) were tested against the (R)- enantiomer. Mean catches were transformed to log(x+1) in order to normalize variances before carrying out analysis of variance (ANOVA). If the F value was significant for treatment (P < 0.05) differences between means were tested for significance by the Games-Howell post-hoc test, using the program SuperANOVA (Abacus Concepts Inc., CA, USA) Y-tube olfactometer experiments using synthetic compounds (Swedish University of Agricultural Sciences, Department of Chemical Ecology, Alnarp, Sweden) (SLU) Males choice to either (R)- or (S)-enantiomer against hexane was tested in the first trial, using a Y-tube olfactometer. In each comparisons 50 males were tested. In the following measurement either an enantimeric mixture in a 9:1 ratio, or in 1:1 ratio (racemic) was compared to (R)-enantiomer per se. In this experiment 30 males were used fro each comparison. A single D. gleditchiae male was introduced into the starting place of the olfactometer, and observed either until he made a choice, or until 3 min. Males that did not choose within 3 min were recorded as no choice, and disregarded. All the experiments with males were carried out between 9 to 12 AM, under 70% humidity and 25 C. Y-tube olfactometer was intensely lighted accordingly to the photophase of honey locust gall midge. For statistical analysis, chi-square test was perfomed. 4

5 2.8. Morphological measurements of antennae using scanning electronmicroscopy (SLU) For preparing the antennae the adults (2-2 male and female) were kept in 96% ethanol, then in acetone for dehydration and finally were glued on a 1 cm wide aluminium platform. The samples were covered with palladium-gold layer (20:80). The mesurements were carried out by means of JOEL 6500LV scanning electronmicroscope. In the focus of attention were the sensillum trichodeum and the sensillum circumfilum, the latter one being unique to gall midges Single sensillum recording SSR (SLU) SSR is an extracellular tecnique for studying the electrophysiological characteristics of a single olfactory sensilla. The action potential pattern (spike) of the stimulated sensillum changes compared to the resting states while it is stimulated with the adequate fragrance, which has receptor in the sensillum. For the experiments the gall midges were fixed on a slide. Analysis was carried out using SSR penetration method. Wolfram fibre electrode was used, previously shaped by electrically saturated KNO 2 solution. The thorax was pierced by one of the electrodes for grounding. The recording electrode was pierced into the base of the chosen sensilla, located on any of the 1st to 4th segments of the antenna. The manipulation was carried out under 200x magnification (Olympus BX51W1), by means of piezoelectric micromanipulator (DC-3K, Märzhäuser, Germany). In case of successful connection, the sensillum were stimulated by either the pheromone or its antipode, in 10 µg dose. The pattern of electric impulse were measured by electrodes, and digitalized by IDAC-4 interface, amplified and analyzed by Autospike32 (Syntech, Hilversum, Netherland) Tracking the occurrence of D. gleditchiae in Skåne, Southern-Sweden (SLU) To check wether D. gleditchiae has already reached Sweden in course of its spread, visual observations of G. triacathos varieties was conducted in several places in Skåne, South Sweden. At a site, the newly developed pheromone traps were also applied and used for season long monitoring, between June November RESULTS 3.1. Mating behaviour Freshly-emerged D. gleditchiae females were observed to keep their ovipositors extended while sitting on fresh leaflets, waiting for males. Otherwise, no specific calling posture was observed. Females were ready to copulate immediately after emergence. Copulations took place most frequently in the morning hours between h under semi-field conditions. Copulations lasted on average for 19.6 sec ± 1.7 sec S.E. (N = 25). After mating, the female withdrew her ovipositor Electroantennographic analysis of collected volatiles The EAG response evoked from the antenna of a male D. gleditchiae by stimulation with a 13 female equivalent (FE) aliquot of a pooled collection of volatiles from altogether 1800 unmated females was mv ± mv S.E., significantly stronger than that of the hexane stimulus (0.043 mv ± mv) (P < 0.05). GC- EAD analysis of a 10 FE aliquot of the volatile collection from females, revealed a single EAG response from the male antenna at min, corresponding to a noticeable peak in the FID trace, and the compound concerned was assumed to possess the pheromonal activity. Retention times of synthetic standards in parallel runs were as follows: decyl acetate 8.80 min; tetradecyl acetate min; hexadecyl acetate min (Figure 1). Thus, the 5

6 retention index (RI) of the EAG-active peak relative to saturated acetates was The amount of the candidate compound present in 1 FE was ca. 50 pg. Fig. 1. Analysis by gas chromatography with simultaneus electroanntennographic detection (GC- EAD) of a colletion of volatile from unmated Dasineura gleditchiae females collected in a closedloop stripping apparatus (CLSA). Analysis of a 10 FE aliquot of the volatile collection revealed a single EAG response from the male antenna at min corresponding to a noticeable peak is the FID trace Structure determination (GC-MS) Structure determination was made by Professor David R. Hall (Natural Resources Institute, University of Greenwich). According to the structure identification the supposed sex pheromone is (2R,8Z)-2-acetoxy-8-heptadecene ((R)-enantiomer of Z8-17:2Ac). The identified sex pheromone is optically active having one chiral center. Based on a stereoselective synthesis Prof. David R. Hall prepared the individual enantiomers. The (R)-enantiomer was in 99,1% and its antipode in 99,0% enantiomeric excess Electroantennography of synthetic compounds Both the racemic (Z)-2-acetoxy-8-heptadecene and the (R)-enantiomer evoked stronger antennal responses (P < 0.05) from male D. gleditchiae than the hexane solvent across the dose range of 1 10 ng. The (S)-enantiomer elicited a stronger response than hexane (P < 0.05) only at the 3 ng dose. The racemic sample evoked stronger responses (P < 0.05) than the (S)-enantiomer at 3 and 10 ng doses. The response evoked by an aliquot of the hexane solution of the collection of volatiles from unmated female D. gleditchiae containing ca. 2.8 ng of the EAD-active component fits well into the range of responses evoked by the (R)- enantiomer at the corresponding dose range Field trapping test using a synthetic compounds In the first experiment, traps baited with (R)-enantiomer of (Z)-2-acetoxy-8-heptadecene attracted significantly higher numbers of D. gleditchiae males than those baited with racemic mixture (P < 0.05) (Table 1). Traps baited with the (S)-enantiomer caught 34 times fewer male midges than those baited with the racemate, although this was still significantly more than those in 6

7 unbaited control traps (P < 0.05). This proved that the natural pheromone is of (R)-configuration, which is highly attractive to conspecific males. Table 1 Mean daily catches of male D. gleditchiae in traps baited with either (R)-, or (S)-enantiomer or racemic Z8-17:2Ac baited traps (Budapest, 1-3 July, 2007, 7 replicates) Compound Dose(µg) Mean catch ± SE* (2R,8Z)-2-acetoxy-8-heptadecen ± 44.2 a (2S,8Z)-2-acetoxy-8-heptadecen ± 0.9 c Racemic (Z)-2-acetoxy-8- heptadecen ± 17.4 b Unbaited ± 0.5 c Total number of caught males: 2147 *Means followed by different letters are significantly different at 5% probalility level after ANOVA on data transformed to log(x+1) followed by the Games-Howell test. In the subsequent trapping experiment, traps baited with racemic mixture (1:1) attracted D. gleditchiae males in lowest numbers, as compared to either a 95:5 mixture, or the (R)-enantiomer, per se, at any of the three dose levels (0.3; 1; 3 µg) (Fig. 2). In all three doses the 95:5 R:S rate enantiomer blend was the most attractive for the males (68.8; 90.7; mean number of captured males/day, resp.). Comparing them to the traps baited with (R)-enantiomer, they catched nearly two times more, but there were still no significant difference (37.4; 50.4; 68.7 mean number of captured males /day, resp.). Dose dependence was noticable within each treatments, as increasing doses resulted increasing catches. Fig. 2. Field trapping: Catches of D. gleditchiae males by traps baited with either racemic mixture, or a 95:5 R:S enantiomeric mixture, or (R)-enantiomer per se, in three doses (0.3; 1; 3 µg). (Lágymányosi-híd, Budapest, 3-13 July 2008) 3.6. Y-tube olfactometer experiments When the hexane-hexane choice was offered, there was no difference between the numbers of males choosing any arms, which shows that the system works correctly (χ 2 =0,6; p<0,5). When comparing enantiomers, (R)-enantiomer of (Z)-2-acetoxy-8-heptadecene was chosen by significantly higher number of males, than the (S)-enantiomer. When comparing the (S)-enantiomer to hexane, there was no differenc in males choice (Table 2). In a subsequent test, a mixure of 9:1 7

8 was chosen by significantly higher number of males than either the racemic mixture, or the (R)- enantiomer per se. Table 2. Paired choice of D. gleditchiae males between either enantiomers of Z8-17:2Ac, or one of the enentiomers versus hexane control, in a Y-olfactometer. Dose (ng) treatment 1/treatment 2 Chisquare sig. R 34 hex 11 χ 2 =0.068 sig. (5%) S 24 hex 21 χ 2 =0.178 n. s. R 31 S 15 χ 2 =9.78 sig. (0.01%) R 34 hex 10 χ 2 =24.04 sig. (0.01%) S 23 hex 21 χ 2 =0.045 n. s. R 23 S 11 χ 2 =7.12 sig. (0.01%) R 31 hex 9 χ 2 =22.05 sig. (0.01%) S 20 hex 20 χ 2 =0 n. s. R 35 S 12 χ 2 =20.59 sig. (0.01%) 3.7. Morphological measurements of antennae using scanning electronmicroscopy (SLU) Both male and female antenna consisted of segments, in addition to the two basal segments, scapus and pedicellus. The male antenna is significantly longer (0.7 ± 0.03 mm), than the female antenna (0.51 ± 0.04 mm) (N=5). There is a marked sexual dimorphism. In males, a segment consists of a connecting part and a swollen node part housing the sensillae. In females, segments has a uniform cylindrical shape. The segments of males are longer (71 µm ± 1.4 µm) than that of the females (50.4 µm ± 1.02 µm) (N=10). On the antennae of both sexes the following three types of chemosensilla were observed: sensillum circumfillum, sensillum trichodeum and sensillum coeloconicum. However the shapes of sensillum circumfillum are different between sexes. Furthermore, two types of mechanosensory sensilla, sensillum cheaticum and terminal sensory peg were noticed Single sensillum recording (SSR) First, the spontaneous activity pattern was observed for sensillum trichoideum. Two different types of spikes were observed, indicating two olfactory receptor cells. Triggering a s. trichoideum by gradually increased doses (0.1; 1; 10 µg) of the (R)-enantiomer the frequency of spikes also increased gradually, and with a significantly higher rate than that of the solvent control. The (S)-enantiomer did not have any effect Tracking the occurrence of D. gleditchiae in Skåne, Southern-Sweden I found first the galls with larvae then the adults of the honey locust gall midge in 2007 in the arboretum of SLU Swedish University of Agricultural Sciences, on G. triacanthos Shademaster and Sunburst, demonstrating the presence of the pest for the first time in Sweden. In 2008, I found the galls also in Malmö and Lund. The seasonal flight pattern of D. gleditchiae was followed in Alnarp using the pheromone trap newly developed in this study. Also, the honey locust gall midge was proved to be a species new to the Swedish fauna. It was a further unexpected finding that I revealed the presence of a mirid bug, Pinalithus cervinus Herrich-Schäffer, and observed that by sucking galls, it controls D. gleditchiae indirectly. 8

9 4. THE PRACTICAL APPLICATION OF THE RESULTS 4.1. Pheromone trap As a practical conclusion, traps baited with a racemic Z8-17:2Ac constitute a powerful tool for monitoring the flight of the honey locust gall midge. In 2010, the honey locust gall midge pheromone trap was actually included as a new member of the Csalomon (Plant Protection Institute, HAS, Budapest, Hungary) traps A new candidate for biological control agent A new possibility in biological control is offered by my result in Alnarp, Sweden, showing that the mirid bug, Pinalithus cervinus occurred in numbers on the infested shoots of G. triacanthos and destroyed en mass the galls of the pest. This mirid species has not been found in Hungary, nevertheless its role as a potential biological control agent should be studied. 9

10 5. NEW SCIENTIFIC RESULTS 1) Calling behaviour and its dial dependence of honey locust gall midge was revealed. Female were ready to copulate immediately after emergence. Adults mated exclusively at the morning hours till noon. The mating lasted for 19.6 ± 1.7 sec. 2) Female emitted sex pheromone was successfully collected using closed loop stripping apparatus (CLSA). For the largest extract ca freshly emerged, unmated females were used. 3) The electrophysiological activity of collected volatiles were proved by electroantennographic detection (EAG). 4) A single antennally active compound was found in the volatile by gas chromatographic coupled to an electroantennographic detection (GC-EAD), with a retention time of min. This information was used for structure elucidation of the pheromone, which was determined as (2R,8Z)- 2-acetoxy-8-heptadecene [(R)-enantiomer of Z8-17:2Ac]. 5) Comparing EAG-responses of the synthetic sex pheromone and its antipode (2S,8Z)-2-acetoxy-8- heptadecene [(S)-enantiomer of Z8-17:2Ac], as well as the racemic mixture, it was found that the (R)-enantiomer evoked significant responses in four dose levels, while the (S)-enantiomer resulted in only negligible low responses, with one exception not differring significantly from that of the hexane solvent. 6) In the field trapping tests, superior captures were recorded at a 95:5 enantiomeric mixture. The (R)-enantiomer attracted significantly higher number of males than the racemic mixture. However, the racemic mixture still resulted in meaningfully high captures. The (S)-enantiomer practically had no effect. For practical monitoring, the racemic mixture can also be considred as a reliable trap bait. 7) In Y-tube olfactometer bioassay, significantly more males chose a 9:1 R:S enantiomeric mixture than either the (R)-enantiomer, or the racemic (1:1) mixture. The number of males choosing the (S)- enantiomer did not differ from that of the hexane. 8) In single sensillum measurements (SSR), it was shown that olfactory receptors of the (R)- enantiomer are housed in the sensillum trichodeum. 9) The honey locust gall midge was found as a species new to the Swedish fauna. Large populations were found in three sites in Southern Sweden (Skåne). 10) A mirid bug (Pinalithus cervinus) was found in numbers, feeding on galls of D. gleditchiae, in Alnarp, Sweden. For cited references: see a list in the Dissertation. 10

11 5. SCIENTIFIC PUBLICATIONS 5.1. Scientific paper in English related to the subject of the dissertation: Molnár, B., Zs. Kárpáti, G. Szőcs, D.R. Hall (2009): Identification of female-produced sex pheromone of the honey locust gall midge, Dasineura gleditchiae. Journal of Chemical Ecology 35: IP: Molnár, B., T. Boddum, G. Szőcs, Y. Hillbur (2008): Occurrence of two ornamental pest gall midges, Obolodiplosis robiniae (Heldman) and Dasineura gleditchiae (Osten Sacken) (Diptera: Cecidomyiidae) in Sweden. Entomologisk Tidskrift 130: Scientific articles in Hungarian related to the subject of the dissertation: Molnár, B.P., G. Szőcs, Y. Hillbur, D.R. Hall (2010): A lepényfa-gubacsszúnyog (Dasineura gleditchiae Osten Sacken) (Diptera: Cecidomyiidae) szexferomonja: izolálás, kémiai meghatározás és szabadföldi csapdázás. (Racemate or enantiomerically optimized blend: which can be recommended as bait of pheromone traps for monitoring the honeylocust gall midge, Dasineura gleditchiae?) Növényvédelem (Plant Protection) 46(3): Posters and oral presentations in English (abstract): Molnár, B., T. Boddum, G. Szőcs, Y. Hillbur (2010): New faunistic records of the honey locust gall midge, by newly developed pheromone traps. 9th European Congress of Entomology Aug Budapest, Hungary, p Molnár, B., Hillbur, Y., Hall, D.R., Szőcs, G. (2009): New perspectives in monitoring gall midges in urban areas: Development of an optimized trap bait for the honey locust gall midge, based on the chiral sex pheromone components. Semio-chemicals without borders Joint conference of the pheromone group of IOBC WPRS/EPRS Nov Budapest, Hungary, p Molnár, B.P., Kárpáti, Zs., Szőcs, G., Hall, D.R. (2007): Identification of the female sex pheromone of the locust bean midge, Dasineura gleditchiae (Dipera: Cecidomyiidae). 23rd International Society of Chemical Ecology, Jena, Germany, Book of Abstract, p Poster and oral presentations in Hungarian (abstract): Molnár, B.P., Y. Hillbur, Szőcs G., David R. Hall (2009): Enantiomer-specifikus receptorok és viselkedési válasz: Mi a szerepe a lepényfa-gubacsszúnyog (Dasineura gleditchiae) feromon komponenseinek? (Enantiomer-specific receptors and behavioral responses: what is the role of the sex pheromone and its antipode?) 55. Növényvédelmi Tudományos Napok, Agrozoológiai Szekció (55th Plant Protection Days, Section of Agrozoology), Budapest, 55:4. Molnár, B. Y. Hillbur, G. Szőcs, David R. Hall (2009): Faunára új gubacsszúnyogok Svédországban: Adaptálható lesz-e a feromoncsapdás előrejelzés? (Gallmidges, new to the Swedish fauna: Can pheromone traps be adopted for monitoring?). 19. Keszthelyi Növényvédelmi Fórum (19th Plant Protection Forum), Keszthely, 19: Molnár, B., Y., Hillbur, G., Szőcs, D.R., Hall (2008): A lepényfa-gubacsszúnyog (Dasineura gleditchiae) párosodási viselkedésének megfigyelése és szexferomonjának meghatározása (Observation of calling behaviour and sex pheromone identification of the honey locust gall midge (Dasineura gleditchiae)). 54. Növényvédelmi Tudományos Napok, Agrozoologiai szekció (54th Plant Protection Days, Section of Agrozoology), Budapest, 54:10. 11

12 5.5. Other scientific articles in English: Z. Kárpáti, B. Molnár, G. Szőcs (2007): Pheromone titer and mating frequency of E- and Z-strains of the european corn borer Ostrinia nubilalis: Fluctuation during scotophase and age dependence. Acta Phytopathol. et Entomol. Hung. 42(1): Posters and oral presentations in English about other scientific topics Kamata, N., Tuda, M., Naka, H., Mori, K., Molnár, B.P., Szőcs, G. (2007): Leucoma candida males attracted to the same stereoisomer of leucomalure in Japan, as L. salicis males in Hungary. 23rd Interantional Society of Chemical Ecology, Jena, Germany, Book of Abstract, p Zs. Kárpáti, B. Molnár, G. Szőcs (2006): Pheromone titer and mating frequency of E- and Z-strains of the European corn borer, Ostrinia nubilalis: Fluctuation during scotophase, and age dependence 8th European Conference of Entomology Sept. 2006, Izmir, Turkey Posters and oral presentations in Hungarian in other scientific topics Molnár, B.P., P. Sallai, K. Balázs, E. Pintér, Z. Fekete, K. Mihályi, Á. Szentesi, G. Szőcs, E. Hummel (2007): Egy botanikai peszticid a NeemAzal T/S hatása alma és meggy kártevőire: Laboratóriumi- és szabadföldi kísérletek három rovarrend képviselőivel. (Effect of NeemAzal T/S damage of sour cherry and apple: Laboratory and field experiments with three insect.) 53. Növényvédelmi Tudományos Napok, Agrozoológiai Szekció, (53rd Plant Protection Days, Section of Agrozoology), Budapest, 53:11. Molnár B., P. Sallai, K. Balázs, E. Pintér, Z. Fekete, K. Mihályi, G. Szőcs, E. Hummel (2006): Egy botanikai peszticid, a NeemAzal T/S szabadföldi alkalmazása lombosfa-fehérmoly (Leucoptera malifolella) ellen, bio-alma ültetvényekben. (Field using one of the botanical pesticide NeemAzal T/S against pear leaf blister moth (Leucoptera malifoliella) in apple orchard). 52. Növényvédelmi Tudományos Napok, Agrozoologiai szekció (52nd Plant Protection Days, Section of Agrozoology), Budapest, 52:16. Kárpáti, Zs., Szőcs, G., Molnár, B. (2006): Egy elfelejtett tápnövény, a vadkomló (Humulus lupulus L.) illatanyagainak elektrofiziológiás és viselkedési hatása a kukoricamoly (Ostrinia nubilalis Hbn.) nőstényeire. (Forgotten host plant, the wild hop s (Humulus lupulus) odours electrophysiological and behavioral effects on the females of the European Corn Borer (Ostrinia nubilalis Hbn.). 52. Növényvédelmi Tudományos Napok, Agrozoologiai szekció (52nd Plant Protection Days, Section of Agrozoology), Budapest, 52: Public science presentations Molnár B.P., Szőcs G. (2011): Csapdában a lepényfa-gubacsszúnyog. (Honey locust gall midge in pheromone trap). Kertészet és Szőlészet (Horticulture and viticulture), 60(17): Molnár, B.P., Szőcs G. (2010): Miért kellene feromoncsapda a szemzésrontó-gubacsszúnyog előrejelzéséhez? (Why should be important a pheromone trap to monitoring the red bug?) Kocsis Kertészet II. Szakmai Nap (2nd Professional Day of Kocsis Horticulture), Szeged-Szőreg. Molnár, B.P., Balázs K., Jenser G., Szőcs G. (2007): Mire lehet jó egy botanikai peszticid? (How can we use one of the botanical pesticide?) Magyar Rovartani Társaság 756. ülése, (Societas Entomogica Hungaricea 756.), Budapest. Molnár, B.P., Sallai P., Balázs K., Pintér E., Fekete Z., Mihályi K., Szőcs G., E. Hummel (2006): Egyes gyümölcskártevők elleni biológiai védekezés hatékony eszköze a NeemAzal T/S készítmény. (Effective biological control against some fruit pests with NeemAzal.) Magyar 12

13 Gyümölcsfaiskolások Országos Egyesülete szakmai továbbképzése, (Alliance of Hungarian Fruitnursery), Gyula. Molnár, B.P., Szentesi Á., Szőcs G., Kerényiné dr. Nemestóthy K., Demeter T., Dobrádi L. (2006): A lepényfa-gubacsszúnyog (Dasineura gleditchiae) életmódja: melyik mozzanat nyújt alkalmat a növényvédelmi beavatkozásra? (Life circle of honey locust gallmidge (Dasineura gleditchiae): Which is the ideal moment to plant protection?) 14. Fővárosi Közterületek Növény-és Talajvédelme konferencia, (14th Soil and Plant Protection of the Public Places of Budapest), Budapest. G. Szőcs, P.B. Molnár, K. Balázs, G. Jenser, P. Sallai, Z. Fekete, Hummel, E. (2006): Egyes gyümölcskártevők elleni védekezés hatékony eszköze a NeemAzal T/S. (Effective biological control against some fruit pests with NeemAzal T/S). Kutatási nap Újfehértón (Research Day in Újfehértó), Újfehértó. Molnár, B.P, P. Sallai, K. Balázs, E. Pintér, Z. Fekete, K. Mihályi, G. Szőcs, K. Nemestóthy, E. Hummel (2005): Díszfáktól az ültetvényekig: Újabb eredmények egy botanikai peszticid, a NeemAzal T/S szabadföldi alkalmazására. (From ornamental plants to the orchards: Recent results of field using one of the botanical pesticide NeemAzal T/S). 13. Fővárosi Közterületek Növény- és Talajvédelme konferencia (13th Soil and Plant Protection of the Public Places of Budapest), Budapest. G. Szőcs, P.B. Molnár, Kenji Mori (2005): Tükröm-tükröm, melyik az én feromonom? Tükörszimmetria és a nyárfa-gyapjaslepke, Leucoma salicis feromon. (Which is my sex pheromone? Optical isomer and pheromone molecule of satin moth, Leucoma salicis.) Magyar Rovartani Társaság 739. (Societas Entomogica Hungaricea 739.) Budapest. 13