Uso de semioquímicos en el control de plagas. Estudios básicos y de aplicación

Los semioquímicos son sustancias implicadas en la comunicación entre seres vivos. En el caso de los insectos, pueden ser herramientas de gran utilidad en la lucha contra plagas, como alternativas a la aplicación de insecticidas convencionales. Son sustancias de gran selectividad y muy activas a baja dosis. Los semioquímicos (feromonas y aleloquímicos) se emplean en el control de plagas tanto para la detección y seguimiento de poblaciones como, de forma directa, en las técnicas de confusión sexual, trampeo masivo y atracción y muerte, entre otras. En la presente tesis se describe la búsqueda y aplicación de semioquímicos para el control de diversas plagas de importancia agronómica, estudiando tres aspectos fundamentales. En primer lugar, el desarrollo y aplicación de la técnica de confusión sexual contra Aonidiella aurantii y Tuta absoluta. En el caso de A. aurantii, se trata de la primera aplicación eficaz de esta técnica contra una plaga de diaspinos y en el caso de T. absoluta, se establecen las condiciones para la aplicación de tratamientos eficaces de confusión sexual. En segundo lugar, se ha estudiado la existencia de valores óptimos de emisión para sistemas basados en la atracción de insectos, aplicado a las plagas Chilo suppressalis, Lobesia botrana, Bactrocera oleae y Ceratitis capitata. En el caso de los lepidópteros C. suppressalis y L. botrana y del tefrítido B. oleae se demostró que la atracción de machos se ve afectada por el nivel de emisión de feromona, de forma que velocidades de emisión por encima y por debajo del nivel óptimo obtenido tienen menor poder atrayente. Sin embargo, respecto a C. capitata, y su paraferomona trimedlure, su respuesta es de tipo asintótico, no se encontró un nivel óptimo y por tanto, mayores dosis de paraferomona atraían al mismo número de machos. La obtención de emisores con velocidades de emisión óptimas es un aspecto poco estudiado en la literatura científica que, sin embargo, es esencial para el desarrollo de los métodos de control basados en la atracción. Como tercera parte de esta tesis, se estudiaron detalladamente los compuestos emitidos por machos y hembras de C. capitata en diversos estadios, para intentar establecer compuestos y mezclas con posible poder atrayente. Para este trabajo se ha utilizado la técnica de microextracción en fase sólida, no empleada hasta el momento para este problema, y la metodología estadística del análisis de componentes principales. La disponibilidad de atrayentes eficaces para hembras de C. capitata supondría una gran ventaja para el control de esta plaga.Vacas González, S. (2011). Uso de semioquímicos en el control de plagas. Estudios básicos y de aplicación [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/12499Palanci

Seasonal variations in essential oil of aerial parts and roots of an Artemisia absinthium L. population from a Spanish area with supramediterranean climate (Teruel, Spain)

[EN] The seasonal variation of essential oil composition of aerial parts and roots of Artemisia absinthium L. has been investigated. It was obtained from individuals growing wild in Teruel (Spain) by means of hydrodistillation (aerial parts) or simultaneous distillation extraction (roots), and analyzed by GC/MS and GC/FID. Results showed a predominance of oxygenated monoterpenes (81.4-89.1%) in aerial parts; mainly (Z)-epoxyocimene (49.3-71.5%), (Z)-chrysanthemyl acetate (7.6-18%) and linalool (0.7-10.4%). In spite of the high intrapopulational variability, significant variations were observed for these three compounds. Root essential oil composition showed a high amount of hydrocarbon monoterpenes (43.8-55.1%) and monoterpenic esters (36.6-41.5%) with a noticeable seasonal stability except for some allelopathic oxygenated monoterpenes. As A. absinthium is a typical invasive species, knowing the seasonal variations of these compounds may be a first step to study their release in soil as a source for natural herbicides.Llorens Molina, JA.; Vacas González, S. (2015). Seasonal variations in essential oil of aerial parts and roots of an Artemisia absinthium L. population from a Spanish area with supramediterranean climate (Teruel, Spain). Journal of Essential Oil Research. 27(5):395-405. doi:10.1080/10412905.2015.1043400S395405275Ariño, A., Arberas, I., Renobales, G., Arriaga, S., & Dominguez, J. B. (1999). Essential Oil ofArtemisia absinthiumL. from the Spanish Pyrenees. Journal of Essential Oil Research, 11(2), 182-184. doi:10.1080/10412905.1999.9701105Abad, M. J., Bedoya, L. M., Apaza, L., & Bermejo, P. (2012). The Artemisia L. Genus: A Review of Bioactive Essential Oils. Molecules, 17(3), 2542-2566. doi:10.3390/molecules17032542Blagojević, P., Radulović, N., Palić, R., & Stojanović, G. (2006). Chemical Composition of the Essential Oils of Serbian Wild-GrowingArtemisia absinthiumandArtemisia vulgaris. Journal of Agricultural and Food Chemistry, 54(13), 4780-4789. doi:10.1021/jf060123oRezaeinodehi, A., & Khangholi, S. (2008). Chemical Composition of the Essential Oil of Artemisia absinthium Growing Wild in Iran. Pakistan Journal of Biological Sciences, 11(6), 946-949. doi:10.3923/pjbs.2008.946.949Carnat, A.-P., Madesclaire, M., Chavignon, O., & Lamaison, J.-L. (1992). cis-Chrysanthenol, A Main Component in Essential Oil ofArtemisia absinthiumL. Growing in Auvergne (Massif Central), France. Journal of Essential Oil Research, 4(5), 487-490. doi:10.1080/10412905.1992.9698115Lopes-Lutz, D., Alviano, D. S., Alviano, C. S., & Kolodziejczyk, P. P. (2008). Screening of chemical composition, antimicrobial and antioxidant activities of Artemisia essential oils. Phytochemistry, 69(8), 1732-1738. doi:10.1016/j.phytochem.2008.02.014Basta, A., Tzakou, O., Couladis, M., & Pavlović, M. (2007). Chemical Composition ofArtemisia absinthiumL. from Greece. Journal of Essential Oil Research, 19(4), 316-318. doi:10.1080/10412905.2007.9699291Ariño, A., Arberas, I., Renobales, G., Arriaga, S., & Domínguez, J. B. (1999). Seasonal Variation in Wormwood (Artemisia absinthiumL.) Essential Oil Composition. Journal of Essential Oil Research, 11(5), 619-622. doi:10.1080/10412905.1999.9701226Goel, D., Goel, R., Singh, V., Ali, M., Mallavarapu, G. R., & Kumar, S. (2007). Composition of the essential oil from the root of Artemisia annua. Journal of Natural Medicines, 61(4), 458-461. doi:10.1007/s11418-007-0175-2Mirjalili, B. F., Meybody, M. H. H., Ardakani, M. M., Rustaiyan, A., Ameri, N., Masoudi, S., & Bamoniri, A. (2006). Chemical Composition of the Essential Oil from Aerial Parts, Leaves, Flowers and Roots ofArtemisia persicaBoiss. from Iran. Journal of Essential Oil Research, 18(5), 544-547. doi:10.1080/10412905.2006.9699162Jassbi, A. R., Zamanizadehnajari, S., & Baldwin, I. T. (2010). Phytotoxic Volatiles in the Roots and Shoots of Artemisia tridentata as Detected by Headspace Solid-phase Microextraction and Gas Chromatographic-mass Spectrometry Analysis. Journal of Chemical Ecology, 36(12), 1398-1407. doi:10.1007/s10886-010-9885-0De Almeida, L. F. R., Frei, F., Mancini, E., De Martino, L., & De Feo, V. (2010). Phytotoxic Activities of Mediterranean Essential Oils. Molecules, 15(6), 4309-4323. doi:10.3390/molecules15064309Zahed, N., Hosni, K., Ben Brahim, N., Kallel, M., & Sebei, H. (2010). Allelopathic effect of Schinus molle essential oils on wheat germination. Acta Physiologiae Plantarum, 32(6), 1221-1227. doi:10.1007/s11738-010-0492-zYoung, G. P., & Bush, J. K. (2009). Assessment of the Allelopathic Potential of Juniperus ashei on Germination and Growth of Bouteloua curtipendula. Journal of Chemical Ecology, 35(1), 74-80. doi:10.1007/s10886-008-9585-1Not Available, N. A., & Duke, S. O. (2003). Ecophysiological aspects of allelopathy. Planta, 217(4), 529-539. doi:10.1007/s00425-003-1054-zAbrahim, D., Braguini, W. L., Kelmer-Bracht, A. M., & Ishii-Iwamoto, E. L. (2000). Journal of Chemical Ecology, 26(3), 611-624. doi:10.1023/a:100546790329

Influence of pheromone emission on the attraction of California red scale males in citrus orchards

[EN] Attraction of California red scale males, Aonidiella aurantii (Maskell), to different release rates of the sex pheromone compound 3-methyl-6-isopropenyl-9-decen-1-yl acetate was evaluated in field trials. This study was aimed to study pheromone emission-response correlations and the existence of an optimum release rate that maximizes trapping efficacy. Release profiles of the pheromone dispensers deployed were determined by gas chromatography to estimate the various emission rates tested. The results reveal that the mean number of A. aurantii males caught correlates with the daily pheromone release rates by means of a quadratic model. The obtained model indicates the existence of a relative maximum of the captures corresponding to an optimum release rate of ca. 300 mu g/day. Higher emission rates (up to 1 g/day) resulted in lower captures. Implications for the mating disruption technique are discussed.The research leading to these results received funding from the Spanish Ministry of Science and Innovation [project number AGL2009-10725].Vacas González, S.; Primo Millo, J.; Navarro-Llopis, V. (2017). Influence of pheromone emission on the attraction of California red scale males in citrus orchards. International Journal of Pest Management. 63(1):10-17. https://doi.org/10.1080/09670874.2016.1209253S1017631Anshelevich, L., Kehat, M., Dunkelblum, E., & Greenberg, S. (1994). Sex Pheromone Traps for Monitoring the European Vine Moth,Lobesia botrana: Effect of Dispenser Type, Pheromone Dose, Field Aging of Dispenser, and Type of Trap on Male Captures. Phytoparasitica, 22(4), 281-290. doi:10.1007/bf02980529Carde, R. T., & Minks, A. K. (1995). Control of Moth Pests by Mating Disruption: Successes and Constraints. Annual Review of Entomology, 40(1), 559-585. doi:10.1146/annurev.en.40.010195.003015Domínguez-Ruiz, J., Sanchis, J., Navarro-Llopis, V., & Primo, J. (2008). A New Long-Life Trimedlure Dispenser for Mediterranean Fruit Fly. Journal of Economic Entomology, 101(4), 1325-1330. doi:10.1603/0022-0493(2008)101[1325:anltdf]2.0.co;2Gardner, P. D., Ervin, R. T., Moreno, D. S., & Baritelle, L. (1983). California Red Scale (Homoptera: Diaspididae): Cost Analysis of A Pheromone Monitoring Program1. Journal of Economic Entomology, 76(3), 601-604. doi:10.1093/jee/76.3.601Gieselmann, M. J., Henrick, C. A., Anderson, R. J., Moreno, D. S., & Roelofs, W. L. (1980). Responses of male California red scale to sex pheromone isomers. Journal of Insect Physiology, 26(3), 179-182. doi:10.1016/0022-1910(80)90078-5Grout, T. G., Toit, D. W. J., Hofmeyr, J. H., & Richards, G. I. (1989). California Red Scale (Homoptera: Diaspididae) Phenology on Citrus in South Africa. Journal of Economic Entomology, 82(3), 793-798. doi:10.1093/jee/82.3.793Grout, T. G., & Richards, G. I. (1991). Value of pheromone traps for predicting infestations of red scale, Aonidiella aurantii (Maskell) (Hom., Diaspididae), limited by natural enemy activity and insecticides used to control citrus thrips, Scirtothrips aurantii Faure (Thys., Thripidae). Journal of Applied Entomology, 111(1-5), 20-27. doi:10.1111/j.1439-0418.1991.tb00290.xJacobson, M., & Beroza, M. (1964). Insect Attractants. Scientific American, 211(2), 20-27. doi:10.1038/scientificamerican0864-20Kennett, C. E., & Hoffmann, R. W. (1985). Seasonal Development of the California Red Scale (Homoptera: Diaspididae) in San Joaquin Valley Citrus Based on Degree-Day Accumulation. Journal of Economic Entomology, 78(1), 73-79. doi:10.1093/jee/78.1.73Knutson, A. E., Harris, M. K., & Millar, J. G. (1998). Effects of Pheromone Dose, Lure Age, and Trap Design on Capture of Male Pecan Nut Casebearer (Lepidoptera: Pyralidae) in Pheromone-Baited Traps. Journal of Economic Entomology, 91(3), 715-722. doi:10.1093/jee/91.3.715McDonough, L. M., Brown, D. F., & Aller, W. C. (1989). Insect sex pheromones. Journal of Chemical Ecology, 15(3), 779-790. doi:10.1007/bf01015176McLaughlin, J. R. (1990). Behavioral response of male white peach scale to the sex pheromone, (R,Z)-3,9,-dimethyl-6-isopropenyl-3,9-decadien-1-ol propionate and corresponding alcohol. Journal of Chemical Ecology, 16(3), 749-756. doi:10.1007/bf01016486Moreno, D. S., Carman, G. E., & Bain, N. S. (1972). Extraction and Bioassay of, and Effect of Solvents on, the Sex Pheromone of the Yellow Scale1, 2. Annals of the Entomological Society of America, 65(5), 1061-1064. doi:10.1093/aesa/65.5.1061Moreno, D. S., Fargerlund, J., & Shaw, J. G. (1973). California Red Scale: Captures of Males in Modified Pheromone Traps13. Journal of Economic Entomology, 66(6), 1333-1333. doi:10.1093/jee/66.6.1333Moreno, D. S., & Kennett, C. E. (1985). Predictive Year-end California Red Scale (Homoptera: Diaspididae) Orange Fruit Infestations Based on Catches of Males in the San Joaquin Valley. Journal of Economic Entomology, 78(1), 1-9. doi:10.1093/jee/78.1.1Navarro-Llopis, V., Sanchis, J., Primo-Millo, J., & Primo-Yúfera, E. (2007). Chemosterilants as control agents of Ceratitis capitata (Diptera: Tephritidae) in field trials. Bulletin of Entomological Research, 97(4), 359-368. doi:10.1017/s0007485307005081Rice, R. E., & Moreno, D. S. (1970). Flight of Male California Red Scale1,2,3. Annals of the Entomological Society of America, 63(1), 91-96. doi:10.1093/aesa/63.1.91Rice, R. E., & Moreno, D. S. (1969). Marking and Recapture of California Red Scale1 for Field Studies3,4. Annals of the Entomological Society of America, 62(3), 558-560. doi:10.1093/aesa/62.3.558Rice, R. E., & Hoyt, S. C. (1980). Response of San Jose Scale 1 to Natural and Synthetic Sex Pheromones. Environmental Entomology, 9(2), 190-194. doi:10.1093/ee/9.2.190ROELOFS, W. L., GIESELMANN, M. J., CARDÉ, A. M., TASHIRO, H., MORENO, D. S., HENRICK, C. A., & ANDERSON, R. J. (1977). Sex pheromone of the California red scale, Aonidiella aurantii. Nature, 267(5613), 698-699. doi:10.1038/267698a0Roelofs, W., Gieselmann, M., Card�, A., Tashiro, H., Moreno, D. S., Henrick, C. A., & Anderson, R. J. (1978). Identification of the California red scale sex pheromone. Journal of Chemical Ecology, 4(2), 211-224. doi:10.1007/bf00988056Samways, M. J. (1988). Comparative monitoring of red scaleAonidiella aurantii(Mask.) (Hom., Diaspididae) and itsAphytisspp. (Hym., Aphelinidae) parasitoids. Journal of Applied Entomology, 105(1-5), 483-489. doi:10.1111/j.1439-0418.1988.tb00214.xShaw, J. G., Moreno, D. S., & Fargerlund, J. (1971). Virgin Female California Red Scales Used to Detect Infestations13. Journal of Economic Entomology, 64(5), 1305-1306. doi:10.1093/jee/64.5.1305Tashiro, H., & Chambers, D. L. (1967). Reproduction in the California Red Scale, Aonidiella aurantii (Homoptera: Diaspididae). I. Discovery and Extraction of a Female Sex Pheromone1,2. Annals of the Entomological Society of America, 60(6), 1166-1170. doi:10.1093/aesa/60.6.1166Vacas, S., Alfaro, C., Navarro-Llopis, V., & Primo, J. (2009). The first account of the mating disruption technique for the control of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae) using new biodegradable dispensers. Bulletin of Entomological Research, 99(4), 415-423. doi:10.1017/s0007485308006470Vacas, S., Alfaro, C., Navarro-Llopis, V., Zarzo, M., & Primo, J. (2009). Study on the Optimum Pheromone Release Rate for Attraction of Chilo suppressalis (Lepidoptera: Pyralidae). Journal of Economic Entomology, 102(3), 1094-1100. doi:10.1603/029.102.0330Vacas, S., Alfaro, C., Navarro-Llopis, V., & Primo, J. (2010). Mating disruption of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae), using biodegradable mesoporous pheromone dispensers. Pest Management Science, 66(7), 745-751. doi:10.1002/ps.1937Vacas, S., Alfaro, C., Primo, J., & Navarro-Llopis, V. (2014). Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus. Journal of Pest Science, 88(2), 321-329. doi:10.1007/s10340-014-0623-1Vacas, S., Miñarro, M., Bosch, M. D., Primo, J., & Navarro-Llopis, V. (2013). Studies on the Codling Moth (Lepidoptera: Tortricidae) Response to Different Codlemone Release Rates. Environmental Entomology, 42(6), 1383-1389. doi:10.1603/en13114Zhang, A., & Amalin, D. (2005). Sex Pheromone of the Female Pink Hibiscus Mealybug,Maconellicoccus hirsutus(Green) (Homoptera: Pseudococcidae): Biological Activity Evaluation. Environmental Entomology, 34(2), 264-270. doi:10.1603/0046-225x-34.2.26

Essential oil composition of leaves of Pistacia lentiscus L. growing wild in Valencia (Spain)

[EN] Pistacia lentiscus L. grows wild in a wide range of habitats in Mediterranean countries. The essential oil (EO) composition of its aerial parts has been extensively studied showing noticeable differences according to plant organ (leaves and twigs or fruits), geographical origin and harvest time. In this study, EO composition of leaves of samples coming from two representative habitats from Valencia (Spain) -siliceous (Segart) and calcicolous (Xeraco) soils-were determined by GC/MS and GC/FID. Hydrocarbon monoterpenes was found the major fraction (57.5 %) in calcicolous soil, whereas hydrocarbon sesquiterpenes was in siliceous soil (39.9 %). Oxygenated monoterpenes reached a significant higher amount in leaves from siliceous location (11.2 %) as against calcicolous one (6.7 %). The rate of oxygenated sesquiterpenes was also higher in siliceous soil (15.2 % in contrast to 1.6 % in calcicolous one. These results lead to consider soil parameters as hypothetical source of EO composition variability being the target for further researches.Llorens Molina, JA.; Vacas González, S.; Sabater Martínez, J. (2015). Essential oil composition of leaves of Pistacia lentiscus L. growing wild in Valencia (Spain). Natural Volatiles and Essential Oils. 2(4):17-26. http://hdl.handle.net/10251/70897S17262

Mating disruption of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae), using biodegradable mesoporous pheromone dispensers

[EN] BACKGROUND: The control of California red scale, Aonidiella aurantii (Maskell), has encountered many difficulties, which has raised interest in alternative control methods. Up to now, the A. aurantii sex pheromone has been used only for monitoring. In a previous work the authors described a biodegradable mesoporous pheromone dispenser for mating disruption. To verify the efficacy of these dispensers, three field trials were conducted, and the results are shown in this paper. RESULTS: The study of the release profile of these dispensers revealed a mean pheromone emission value of 269 mu g day(-1) and levels of residual pheromone of 10% at the end of 250 days. During the second flight, an A. aurantii male catch reduction of 98% was achieved in the mating disruption plot of trial 1,93.5% in trial 2 and 76.7% in trial 3. During the third flight, reductions were 94.1, 82.9 and 68.1% in trials 1, 2 and 3 respectively. Considering damaged fruit with more than five scales, reductions of about 80 and 60% were obtained in the mating disruption plots of trials 2 and 3, respectively, compared with an untreated plot, and a reduction of about 70% in trial 1 compared with an oil-treated plot. CONCLUSION: Mating disruption has been found to be an efficient technique to control this pest, working equally well to a correctly sprayed oil treatment. Further studies are needed to improve the determination of the time of dispenser application and evaluate the effects of the pheromone on natural enemies. (C) 2010 Society of Chemical IndustryThe authors are grateful to Ernesto Machancoses and Vicente Morato (Picasent) and to Antonio Caballero from Rio Tinto Fruits ´ for facilitating study orchards and assisting with the collection of trapping data. This research has been supported by Ministerio de Ciencia y Tecnología project number AGL 2009-10725.Vacas González, S.; Alfaro Cañamás, C.; Navarro-Llopis, V.; Primo Millo, J. (2010). Mating disruption of California red scale, Aonidiella aurantii Maskell (Homoptera: Diaspididae), using biodegradable mesoporous pheromone dispensers. Pest Management Science. 66(7):745-751. https://doi.org/10.1002/ps.1937S74575166

Mating disruption to control the striped rice stem borer: Pheromone blend, dispensing technology and number of releasing points

The effect of using low densities of different dispensing technologies on mating disruption of the striped rice stem borer, Chilo suppressalis Walker, was evaluated in the rice-growing area of Valencia (Spain) from 2011 to 2013. The reduction of the current number of release points (30 polymeric dispensers/ha) was investigated by installing 3 aerosol devices per ha (Experiments 1 and 2) or with clusters of hand-applied dispensers (10 or 5 release points/ha; Experiment 3). The influence of pheromone blend on disruption was also studied by loading aerosol devices with the three-component blend or only the main pheromone compound, Z-11-hexadecenal. Results showed that the installation of 3 aerosol devices/ha or clusters of passive dispensers (total dose: 6.6-7.9 g/ha) proved equally effective as the conventional treatment with 30 Selibate (R) CS dispensers/ha (similar to 5 g/ha), reducing damage below 1% of infested plants. Although the treatment with 3 aerosol devices/ha loaded with Z-11-hexadecenal provided control of damage comparable to the conventional mating disruption treatment, the higher captures recorded suggest that mating disruption with the incomplete pheromone blend is only slightly effective in the tested conditions. These changes in the number of point sources and pheromone blend could represent important advantages for the implementation of mating disruption against C. suppressalis. (C) 2016 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved.We would like to thank Francisco Girona, Vicente Dalmau and Manuel Lainez (CAPA-Generalitat Valenciana) for their assistance in organizing experiments and providing trial fields. In addition, thanks to Helen Warburton for English editing. This project was funded by Fundacion Agroalimed and Ecologia y Protection Agricola SL (Valencia, Spain).Vacas González, S.; Navarro Fuertes, I.; Primo Millo, J.; Navarro-Llopis, V. (2016). Mating disruption to control the striped rice stem borer: Pheromone blend, dispensing technology and number of releasing points. Journal of Asia-Pacific Entomology. 19(2):253-259. doi:10.1016/j.aspen.2016.02.001S25325919

Response of two tephritid species, Bactrocera oleae and Ceratitis capitata, to different emission levels of pheromone and parapheromone

Attractants and pheromones are commonly used in integrated pest management programs in crop systems. However, pheromone dispensers employed in monitoring traps and lure and kill devices are not usually well studied and attractants are released at uncontrolled rates leading to low treatment efficacies and misleading monitoring estimations. Fruit flies are pests of economic importance and monitoring is essential in order to program insecticidal treatments. Moreover, lure and kill techniques are being increasingly used, but the cost of these techniques depends on the number of required traps and, therefore, on the efficacy of the attractants. Ceratitis capitata and Bactrocera oleae are the two main fruit flies in Mediterranean countries, and the effect of different doses of trimedlure and spiroacetal on fly attraction has been studied. Results showed that a release rate over 1.28 mg/day of spiroacetal reduces B. oleae attraction and emission values over 2.4 mg of trimedlure per day did not increase C. capitata catches. Under the environmental conditions of our study, an optimum release rate for pheromone attraction in B. oleae was determined. Emission values over this optimum level reduced B. oleae attraction. However, when a parapheromone was used with C. capitata, a fruit fly of the same family, the optimum emission value was not found and higher quantities of parapheromone attracted the same number of flies. The saturation effect of high concentrations of pheromone and parapheromone is discussed.We wish to thank "Cartuja de Portacoeli" and Domingo de Guzman Orero for offering their orchards for this research, and Juan Bautista for field assistance. This research was supported by "Ministerio de Ciencia e Innovacion" project number AGL2006-13346-C02-02.Navarro Llopis, V.; Alfaro Cañamás, C.; Primo Millo, J.; Vacas González, S. (2011). Response of two tephritid species, Bactrocera oleae and Ceratitis capitata, to different emission levels of pheromone and parapheromone. Crop Protection. 30(7):913-918. https://doi.org/10.1016/j.cropro.2011.03.007S91391830

Studies on the development of a mating disruption system to control the tomato leafminer, Tuta absoluta Povolny (Lepidoptera: Gelechiidae)

BACKGROUND: The tomato leafminer (Tuta absoluta Povolny) has rapidly colonised the whole Mediterranean and South-Atlantic coasts of Spain, and it has become a key problem in both outdoor and greenhouse crops. New control methods compatible with biological control are required, and mating disruption appears to be a perfect method in current agriculture, as it is an environmentally friendly and residue-free technique. IPM packages tested have included the use of pheromones to detect populations, but there has not been much previous research on mating disruption of T. absoluta. In this work, pheromone doses varying from 10 to 40 g ha(-1), emitted at a constant rate over 4 months, were tested in greenhouses with different levels of containment in order to evaluate the efficacy of mating disruption on T. absoluta. RESULTS: Trials on containment level revealed that the flight of T. absoluta was satisfactorily disrupted with an initial pheromone dose of 30 g ha(-1), and levels of damage did not significantly differ from those in reference plots with insecticide treatments. Later efficacy trials confirmed previous experiences, and release studies showed that control of damage and flight disruption were taking place when releasing at least 85 mg pheromone per ha per day. CONCLUSION: Effective control using pheromone application against T. absoluta can be achieved, in greenhouses with high containment levels, for 4 months, with initial doses of 30 g ha(-1). Further research must be conducted in order to evaluate the prospect of outdoor application of mating disruption systems.Vacas González, S.; Alfaro Cañamás, C.; Primo Millo, J.; Navarro-Llopis, V. (2011). Studies on the development of a mating disruption system to control the tomato leafminer, Tuta absoluta Povolny (Lepidoptera: Gelechiidae). Pest Management Science. 67(11):1473-1480. doi:10.1002/ps.2202S14731480671

Studies on the Codling Moth (Lepidoptera: Tortricidae) Response to Different Codlemone Release Rates

[EN] The response of the codling moth (Cydia pomonella L. (Lepidoptera: Tortricidae)) to different emission values of its main pheromone component, 8E,10E-dodecadien-1-ol (codlemone), was investigated in three field trials conducted in plots without mating disruption treatments. Moth catches obtained in traps baited with pheromone dispensers were correlated with the corresponding codlemone release rates by multiple regression analysis. In a preliminary trial conducted in Lleida (NE Spain), a decreasing trend of captures was observed based on increasing pheromone levels. After this, the pheromone release profiles of the pheromone dispensers were studied, in parallel with the field trials, by residual codlemone extraction and gas chromatography quantification. In the trials carried out in Asturias (NW Spain), a correlation between trap catches and emission levels (within the range from 11 to 1,078 microg/d) was found and fitted a logarithmic model. Captures followed a decreasing linear trend in the range of emission rates from 11 to 134 microg/d. Given that release values comprised between 11 and 67 mcrog/d did not lead to significantly different catches in traps, this emission range could be considered to develop effective formulations for attraction purposes when mating disruption is not acting in the environment.Vacas González, S.; Miñarro, M.; Bosch, M.; Primo Millo, J.; Navarro Llopis, V. (2013). Studies on the Codling Moth (Lepidoptera: Tortricidae) Response to Different Codlemone Release Rates. ENVIRONMENTAL ENTOMOLOGY. 42(6):1383-1389. doi:10.1603/EN13114S1383138942

Variability of essential oil composition of wormwood (Artemisia absinthium L.) affected byplant organ

The essential oil composition of leaves and roots of twenty individuals of wormwood (Artemisia absinthium L.) belonging to different chemotypes has been investigated. They were obtained from two accesions coming from Hungarian and Spanish wild populations. Essential oils were extracted by hydrodistillation and analyzed by GC/MS and GC/FID. Results showed a great individual variability of wormwood accesions. Based on leaves, three chemotypes (sabinene + myrcene, -thujone and new sesquiterpene type accounting up to 80.8% of sesquiterpenic fraction) were found in the Hungarian population and two chemotypes ((Z)--epoxyocimene and (Z)--epoxyocimene + (Z)-chrysanthemyl acetate types) were present in the Spanish one. The composition of EO of the roots from both locations was predominated by monoterpenic esters (14.5-80.2% and 59.9-90.3%, in Hungarian and Spanish samples respectively) but characteristic quantitative and qualitative differences were present. No relationship was found between the composition of EO of roots and leaves of the same plant.Llorens Molina, JA.; Vacas González, S.; Castell Zeising, V.; Németh Zámboriné, É. (2016). Variability of essential oil composition of wormwood (Artemisia absinthium L.) affected byplant organ. Journal of Essential Oil Research. 29(1):11-21. doi:10.1080/10412905.2016.1202152S112129